KANSAS
KANSAS AGRICULTURAL STATISTICS
Room 200, 632 S.W. Van Buren, Topeka, KS 66603, USA.
E.J. Thiessen
Jagger becomes most popular cultivar.
Jagger was the leading cultivar of wheat seeded in Kansas for the 1998 crop,
according to Kansas Agricultural Statistics (see Fig.
1). Jagger was popular in all districts, accounting for 20.2 % of the
state's wheat. Kansas State University-maintained cultivar 2137 ranked second
overall, with 13.5 % of the acreage. 2137 was the second leading cultivar
in the central district and ranked in the top five in all districts but
the northwest. TAM 107 dropped to third position, with 12.6 % of the acreage.
TAM 107 was the dominant cultivar planted in the western third of the state.
Karl and improved Karl dropped to the fourth leading cultivars seeded in
Kansas, accounting for 10.8 % of the acreage statewide, and were popular
in the north central and eastern one-third of the state. The fifth most
popular cultivar was 2163, with 10.5 % of the state's acreage. The KSU-maintained
cultivar 2163 ranked in the top five varieties in all but the western districts
of the state. Ike dropped from fourth most popular wheat to sixth, with
7.0 %. Seventh was Agseco 7853, with 3.4 %. Larned dropped one place to
eighth, with 2.4 %. Rounding out the top 10 were AgriPro Tomahawk and AgriPro
Pecos, with 1.8 and 1.6 %, respectively. Blends were popular in the central
one third of the state, accounting for 2.8 % of the acres planted.
Publications.
Monthly Crop. Wheat cultivars, percent of acreage devoted to each cultivar.
Wheat quality, test weight, moisture, and protein content of current harvest.
$10.00
Crop-Weather. Issued each Monday, March 1 through November 30 and monthly, December through February. Provides crop and weather information for previous week. $12.00
County Estimates. County data on wheat acreage seeded and harvested, yield, and production on summer fallow, irrigated, and continuous cropped land. December.
Wheat Quality. County data on protein, test weight, moisture, grade, and dockage. Includes milling and baking tests, by cultivar, from a probability sample of Kansas wheat. September.
Each of the above reports is available on the Internet at the following
address: http://www.nass.usda.gov/ks/
Reports available via E-mail and how to subscribe.
A list of all SSO reports that are available via E-mail can be found on
the Internet at http://www.nass.usda.gov/sub-form.htm, which provides
for automated subscribing. The reports are provided without charge. To subscribe
to one or more of the reports listed, follow the instructions on the automated
form.
DEPARTMENTS OF AGRONOMY AND BIOCHEMISTRY
Throckmorton and King Halls, Manhattan, KS 66506-5501, USA.
Wheat transformation mediated by Agrobacterium tumefaciens.
Q.L. Mi 1, R. Velazhahan 2, S. Muthukrishnan 2, and G.H. Liang 1.
1 Department of Agronomy and 2 Department of Biochemistry.
An improved protocol has been developed for the production of transgenic wheat using Agrobacterium-mediated gene transfer. A cDNA coding for a 24.4 kDa thaumatin-like protein (TLP) from rice was used for transformation of wheat. TLPs are another group of pathognensis-related proteins (PR-5 group), which are postulated to play a role in plant defense. The 2-week-old scutellar calli derived from immature embryos were cocultivated with the A. tumefaciens strain LBA4404, which carries a binary vector pMON 410 containing the hygromycin gene, and a rice TLP gene under the control of the CaMV35S promoter.
Inclusion of acetosyringone in the Agrobacterium suspension and coculture medium is necessary for successful transformation. The highest frequencies of regeneration and transformation were obtained when selection culture was in 75 mg/l hygromycin after cocultivation was limited to 2 weeks in the dark, followed by regeneration in hygromycin-free medium under light. The plantlets then were transferred to rooting medium (hormone-free half strength MS medium) containing 50 mg/l hygromycin, which was found to increase the recovery of transformed plants. Using those conditions, more than 20 morphologically normal and fertile transformed wheat plants were obtained from 1,700 embryogenic calli of Pavon76, Bobwhite, and Jagger within 3 months after the initiation of cultures.
Expression of the rice TLP gene in transgenic wheat was confirmed by Western blot analysis of leaf extracts. From eight R0 plants of Pavon76 regenerated from calli, the presence of a rice TLP with an apparent molecular weight of 24.4 kDa was detected in six plants with a TLP antibody. Among eight R0 plants of Bobwhite, five plants showed the 24.4 kDa band. Among seven R0 plants of Jagger, five plants also showed the 24.4 kDa band.
The intergration of the rice TLP gene into the wheat genome was confirmed by Southern blot analysis of the R0 transgenic plants that had positive reactions in the Western blot analysis.
Publications.
Gu X and Liang GH. 1997. Plantlet regeneration from protoplast-derived haploid embryogenic calli of wheat. Plant Cell, Tissue and Organ Cult 50:139-145.
Mi QL, Velazhahan R, Mushukrishnan S, and Liang GH. 1997. Wheat transformation mediated by Agrobacterium tumefaciens. Agron Abstr p. 147.
Liang GH, Skinner DZ, Sun Y, Sorensen EL, and Guo JH. 1997. The Discovery of Mendel's Laws. Chapter 11. In: Discoveries in Plant Biology (Kung SD and Yang HF eds). World Sci Publ Co, Singapore.
EVAPOTRANSPIRATION LABORATORY
Department of Agronomy, Waters Hall, Kansas State University, Manhattan, KS 66502, USA.
M.B. Kirkham.
A dual-probe heat-pulse technique to measure soil water and temperature
in soil with roots.
Volumetric water content and temperature were measured in soil with dual-probe
heat-pulse (DPHP) sensors to determine distributions of these parameters
in the presence of numerous roots. Three experiments were carried out in
columns (20 cm in diameter; 12 or 16 cm deep) containing a Haynie very fine
sandy loam with tall fescue (Festuca arundinacea Schreb.).
Sensors were placed horizontally at different distances from the soil surface
(vertical direction) and at different distances from the axis of the columns
(radial direction). The DPHP sensors monitored soil water content within
1.5 cm of the soil surface and over a wide range of moisture contents (0.44
to 0.9 m3/m3). The sensors allowed 2-dimensional spatial distributions of
water and temperature to be determined on a small scale (every 3 cm with
depth and 1.46 cm apart radially). Essentially uniform distributions of
water and temperature were observed laterally. Soil was drier (up to 0.07
m3/m3 drier) and cooler (up to 1°C) at the surface than at deeper depths.
The results for water distribution substantiate the observation that water
in agricultural soils changes more in the vertical, than the horizontal,
direction because roots grow down. (This work was by graduate student Yan
Song and Prof. M.B. Kirkham, in coöperation with J.M. Ham and G.J.
Kluitenberg.)
Publications.
Kirkham MB and Erickson PI. 1997. Physical model for movement of water in
split-root wheat plants. Inter Agrophysics 11:207-214.
Kirkham MB, Grecu SJ, and Kanemasu ET. 1998. Comparison of minirhizotrons and the soil-water-depletion method to determine maize and soybean root length and depth. Eur J Agron (in press).
Song Y, Kirkham MB, Ham JM, and Kluitenberg GJ. 1998. Volumetric water content and temperature measurement in soil with turfgrass using the dual-probe heat-pulse technique. In: Characterization and Measurement of the Hydraulic Properties of Unsaturated Porous Media (van Genuchten MT ed). University of California Press, Riverside. (In press).
THE WHEAT GENETICS RESOURCE CENTERDepartment of Plant Pathology, Throckmorton Hall, Kansas State University, Manhattan, KS 66506-5502, USA.
The Wheat Genetics Resource Center update.
W.J. Raupp and B.S. Gill.
Within the last few decades, the conservation of plant genetic resources
has taken on great importance. Although in situ conservation
is preferential, it is estimated that one-third of the world's germ plasm
is housed in ex situ collections. The collection of wheat germ plasm
maintained by the Wheat Genetics Resource Center (WGRC) at Kansas State
University is a composite of collections from existing sources. In total,
over 2,600 accessions of wild wheat species and 2,300 genetic stocks currently
are maintained in the WGRC gene bank. Collection and characterization information
is maintained and accessible through internet access via GrainGenes, the
small grains database for wheat and sugarcane, and from the WGRC. Because
as much as three-fold duplication may exist worldwide in the collection
of Triticeae, it is now more important than ever that we begin to assess
the world's wheat germ plasm. Several efforts have been initiated in Europe
and Asia, but none that we are aware of in the U.S. We have surveyed the
USDA collection and have crossreferenced a significant percent of our collection.
In this survey, we also discovered previously undetected duplications in
the WGRC collection. We now want to coördinate this effort with other
major gene banks in the U.S. and around the world, especially those with
germ plasm holdings of wild Triticeae species.
Transfer of disease resistance genes from Triticum timopheevii
ssp. armeniacum to common wheat.
G.L. Brown-Guedira, B.S. Gill, T.S. Cox, and S. Leath.
The wild tetraploid wheat species T. timopheevii ssp. armeniacum is a source of pest resistance genes for T. aestivum. Our objectives were to describe the breeding behavior of T. timopheevii ssp. armeniacum when backcrossed to common wheat and to transfer resistant to leaf rust and powdery mildew to wheat. Crosses were made between five wheat gentoypes and 12 T. timopheevii ssp. armeniacum accessions. Fertility and chromosome numbers of BC1F1, BC2F1, and BC3F1 plants were determined. Resistance to leaf rust was transferred to BC2 derived families from 10 different T. timopheevii var. armeniacum accessions. Leaf rust resistance genes in nine T T. timopheevii ssp. armeniacum accessions can be assigned to at least four loci. Leaf rust resistance transferred from three accessions was inherited in the hexaploid derivatives as a single, dominant gene in each case. Resistance to powdery mildew also was detected in the T. timopheevii ssp. armeniacum backcross derivatives. Fertile hexaploid derivatives expressing T. timopheevii ssp. armeniacum-derived resistance genes can be recovered after two backcrosses to wheat cultivars.
Grain yield and bread-making quality of wheat lines with the leaf
rust resistance gene Lr41.
T.S. Cox, R.K. Bequette, R.L. Bowden, and R.G. Sears.
Some of the many disease-resistance genes transferred into common wheat by interspecific hybridization have been underutilized in agriculture because of associated negative effects on productivity and end-use quality. The Lr41 gene conferring resistance to leaf rust was transferred from wild diploid goatgrass (Ae. tauschii), the chromosomes of which recombine readily with those of common wheat. Thus , its chromosomes recombine readily with those of wheat. This study had three objectives: (i) to determine the direct and linked effects of Lr41 on 15 productivity and quality traits in HRWW under disease-free conditions; (ii) to determine the effects of resistance conferred by Lr41 under a severe leaf rust epidemic and under a light infection; and (iii) to determine the amount of damage inflicted by diseases other than leaf rust in those environments. Six BC2F2-derived common wheat lines with Lr41, along with their recurrent parents (HRWW cultivars TAM 107, TAM 200, and Century), were evaluated in three field experiments with and without fungicide treatment in 1992 and 1994. Lr41 increased grain yield and milling quality under heavy leaf rust infection with no negative effects on those traits in disease-free plots. However, Lr41 was associated with reduced bake-mixing time and water absorption in the absence of disease. Effects of other diseases depended heavily upon the genetic backgrounds (i.e., recurrent parents) of backcross lines. There should be no serious impediments to the use of Lr41 in breeding programs.
RFLP mapping of resistance to chlorosis induction by Pyrenophora tritici-repentis
in wheat.
J.D. Faris, J.A. Anderson, L.J. Francl, and J.G. Jordahl.
Tan spot is an economically important disease in major wheat production areas. The fungus can produce two genetically distinct symptoms on leaves of susceptible wheat genotypes: tan necrosis (nec) and extensive chlorosis (chl). Our objectives were to determine the number of genes conditioning resistance to tan spot in a population of wheat recombinant inbred lines, and map the chromosomal location of the resistance genes using RFLPs. Conidia produced by the P. tritici-repentis isolate Pti2 (nec + chl +) were used to inoculate seedlings of 135 recombinant inbred lines derived from the cross of the synthetic hexaploid wheat W-7984 with Opata 85. A subset of the population was inoculated with conidia produced by the isolates D308 (nec - chl +) and 86-124 (nec + chl -). Inoculated seedlings were rated on a scale of 1 to 5, based on lesion type. Necrosis-inducing culture filtrate produced by the isolate 86-124 also was used to screen the entire population. A map consisting of 532 markers was employed to identify significant associations between marker loci and tan spot resistance. The entire population was insensitive to the culture filtrate produced by isolate 86-124, and the entire subset was resistant to conidial inoculation of the same isolate. The population segregated for reaction to isolates D308 and Pti2, indicating that this population segregates for resistance to extensive chlorosis only and not to tan necrosis. RFLP analysis indicated the presence of a gene with a major effect on 1AS, a gene with a minor effect on 4AL, and an interaction between the 1AS gene and a gene on 2DL. Together, these loci explained 49.0 % of the variation in this population for resistance to tan spot produced by the isolate Pti2. Two regions, one on 1BL and one on 3BL, were associated significantly with resistance to extensive chlorosis but were not significant in the multiple regression model. Itrogression of these resistance loci into adapted genetic backgrounds should be feasible using a marker-assisted selection scheme.
Chromosome location of leaf rust resistance gene Lr43 from Aegilops
tauschii in common wheat.
T. Hussein, R.L. Bowden, B.S. Gill, and T.S. Cox.
Wheat leaf rust resistance gene Lr43 was transferred recently from Ae. tauschii to common wheat to produce hard red winter wheat germ plasm line KS92WGRC16. Monosomic and telocentric analyses were used to determine the chromosomal and chromosome arm location of Lr43. KS92WGRC16 was crossed with each of the seven D-genome monosomic lines. The F2 families were inoculated with race PBJL of the leaf rust fungus. The number of resistant to susceptible seedlings did not deviate significantly from a 3:1 ratio in crosses involving 1D, 2D, 3D, 4D, 5D, and 6D monosomic lines. However, the 7D monosomic-derived F2 deviated significantly from a 3:1 ratio (X2 = 32.2, P < 0.001) indicating that Lr43 is located on this chromosome. Twenty resistant F2 plants from the critical cross were progeny tested, and results confirmed the location of Lr43 on chromosome 7D. Telocentric analysis showed that Lr43 is on the short arm of chromosome 7D (7DS), and it is unlinked to the centromere. This information may facilitate development of molecular markers and result in more efficient breeding for resistant cultivars.
Performance of four new leaf rust resistance genes transferred to
common wheat from Aegilops tauschii and Triticum monococcum.
T. Hussein, R.L. Bowden, B.S. Gill, T.S. Cox, and D.S. Marshall.
The objective of this study was to test the performance of four new wheat leaf rust resistance genes previously transferred from wild relatives of common wheat. Leaf rust resistance gene Lr43, in wheat germ plasm line KS92WGRC16, was originally from Ae. tauschii. A second resistance gene, in line KS92WGRC23, was transferred from T. monococcum ssp. monococcum. Two other genes, in lines KS93U3 and KS96WGRC34, were obtained from T. monococcum ssp. aegilopoides. In greenhouse tests, the typical low infection types produced by these lines were fleck (;), immune (0), fleck with chlorosis (;C), and heterogeneous (X-) for KS92WGRC16, KS92WGRC23, KS96WGRC34, and KS93U3, respectively. In field tests in Kansas and Texas, KS92WGRC23 and KS92WGRC16 were highly resistant. KS93U3 was moderately resistant in Kansas but moderately resistant to moderately susceptible in Texas. KS96WGRC34 was moderately resistant in Kansas but moderately resistant to susceptible in Texas. Greenhouse adult-plant tests with race PBJL of P. recondita indicated that KS92WGRC16, KS92WGRC23, and KS96WGRC34 were highly resistant, but KS93U3 gave a moderately resistant reaction. Growth-chamber studies in different environments (12, 16, 20, and 24°C) showed slight temperature effects on the expression of resistance in KS96WGRC34 but not in the other lines. Tests with nine races of P. recondita indicated that only KS92WGRC16 was resistant to all races. Races PNML and PNMQ were virulent on KS92WGRC23, and race TFGL was virulent on both KS93U3 and KS96WGRC34. The genes in the four germ plasm lines should be used in combination with other resistance genes to prolong their usefulness.
Molecular cytogenetic analysis of Leymus racemosus chromosomes added
to wheat.
L.L. Qi, S.L. Wang, P.D. Chen, D.J. Liu, B. Friebe, and B.S. Gill.
Five disomic, two double-disomic, and two ditelosomic addition lines
and one disomic substitution line derived from the crosses of 'T. aestivum
/ Leymus racemosus (2n = 4x = 28, JJNN)' were identified by C-banding
analysis. The homoeology of the added Leymus chromosomes was determined
by RFLP analysis. Four of the five disomic addition lines belonged to group
2, 5, 6, and 7 chromosomes of L. racemosus; these were designated
as 2Lr#1(NAU516), 5Lr#1 (NAU504, NAU514), 6Lr#1 (NAU512), and 7Lr#1 (NAU501).
Two additional chromosomes, 1Lr#1 and 3Lr#3, were present in double-disomic
addition lines 1Lr#1 + 5Lr#1 (NAU525) and 3Lr#1 + 7Lr#1 (NAU524), respectively.
In the disomic substitution line, wheat chromosome 2B was replaced by L.
racemosus chromosome 2Lr#1 (NAU551). Two telocentric chromosomes, 2Lr#2S
(NAU509) and 7Lr#1S (NAU511), were isolated as ditelosomic addition lines.
The study presented here provides the first evidence of homoeology of the
added L. racemosus chromosomes with wheat chromosomes using DNA markers.
Our data provide the basis for further directed chromosome engineering aimed
at producing compensating wheatL. racemosus translocation lines.
Publications.
Brown-Guedira GL, Gill BS, Cox TS, and Leath S. 1997. Transfer of disease
resistance genes from Triticum araraticum to common wheat.
Plant Breed 116:105-112.
Cox TS, Bequette RK, Bowden RL, and Sears RG. 1997. Grain yield and breadmaking quality of wheat lines with the leaf rust resistance gene Lr41. Crop Sci 37:154-161.
Cox TS, Hussien T, Sears RG, and Gill BS. 1997. Registration of KS92WGRC16 winter wheat germplasm resistant to leaf rust. Crop Sci 37:634.
Faris JD, Anderson JA, Francl LJ, and Jordahl JG. 1997. RFLP mapping of resistance to chlorosis induction by Pyrenophora tritici-repentis in wheat. Theor Appl Genet 94:98-103.
Faris JD, Laddomada B, Boiko EV, Gill KS, and Gill BS. 1997. Sex, segregation, and recombination in Aegilops tauschii. PAG V (abstract).
Gill BS, Gill KS, Friebe B, and Endo TR. 1997. Expanding genetic maps: reevaluation of the relationship between chiasmata and crossovers. In: Chromosomes Today Volume 12 (Henriques-Gil N, Parker JS, and Puertas MJ eds). Chapman and Hall, London. pp. 283-298.
Gornicki P, Faris J, King I, Podkowinski J, Gill BS, and Haselkorn R. 1997. Plastid localized acetyl-CoA carboxylase of bread wheat is encoded by a single gene on each of the three ancestral chromosome sets. Proc Natl Acac Sci USA 94:14179-14184.
Hussein T, Bowden RL, Gill BS, and Cox TS. 1997. Chromosome location of leaf rust resistance gene Lr43 from Aegilops tauschii in common wheat. Crop Sci 37:1764-1766.
Hussein T, Bowden RL, Gill BS, Cox TS, and Marshall DS. 1997. Performance of four new leaf rust resistance genes transferred to common wheat from Aegilops tauschii and Triticum monococcum. Plant Dis 81:582-586.
Jackson SA, Friebe B, Gill BS, and Jiang J. 1997. Structure of the rye midget chromosome analyzed by FISH and C-banding. Genome 40:782-784.
Qi LL, Wang SL, Chen PD, Liu DJ, Friebe B, and Gill BS. 1997. Molecular cytogenetic analysis of Leymus racemosus chromosomes added to wheat. Theor Appl Genet 95:1084-1091.
Raupp WJ, Friebe B, and Gill BS. 1997. The Wheat Genetics Resource Center current status, future direction. Proc 3rd Inter Triticeae Symp, Aleppo, Syria. 4-8 May, 1997. p. 34 (in press).
Raupp WJ, Friebe B, Wilson DL, Cox TS, and Gill BS. 1997. Kansas State's
Wheat Genetics Resource Center provides unique oasis for germplasm research.
Focus on documenting genetic diversity of wild wheats. Diversity 13:21-23.
Sebesta EE, Hatchett JH, Friebe B, Gill BS, Cox TS, and Sears RG. 1997.
Registration of KS92WGRC17, KS92WGRC18, KS92WGRC19, and KS92WGRC20 winter
wheat germplasms resistant to Hessian fly. Crop Sci 37:635.
O.K. Chung, G.L. Lookhart, J.L. Steele, S.R. Bean, F.E. Dowell, J.B. Ohm, H.S. Park, I.Y. Zayas, D.W. Hagstrum, P.W. Flinn, D.B. Bechtel, C.R. Martin, L.M. Seitz, S.H. Park, B.W. Seabourn, D. Wang, C.S. Chang, M.S. Ram, J.D. Wilson, M.D. Shogren, R.E. Dempster, M.S. Caley, D.B. Sauer, J.D. Hubbard, J.M. Downing, J.E. Throne, J.E. Baker, R.K. Lyne, S.K. Akkina, R. Rengarajan, X. Liu, Z.L. Haden, D.L. Brabec, K.T. Fay, Z.S. Xiao, and D.E. Koeltzow.
Wheat quality for different products
Wheat quality means many different things to varied groups; to a wheat farmer
it is yield; to the miller it is consistency; to the baker it is crumb grain;
to the breeder it is resistance; and to the cereal chemist it is unique
proteins, lipids, enzymes, and starch. Wheat quality has numerous components
and each is related to the user's preferences. Wheat is unique among all
the food grains. Wheat alone has the visco-elastic dough properties that
are essential to making the many food products that are favored in our diet.
The range of these foods is wide, depending on the geographical location
and culture of the consumer. In western countries, leavened pan bread is
the obvious wheat-based food, but this form now also is common worldwide.
Wheat also is the basis of many breakfast cereals, cookies, and cakes, and
it is an important ingredient of many processed foods. Pasta is another
common form of wheat-based food. More common in the Middle East is the wide
range of flat and pocket breads. The many forms of noodles are most evident
in Asia, together with steamed breads. Each of these products requires a
distinct type of wheat with defined quality attributes, i.e., specific combinations
of grain hardness, gluten strength and extensibility, starch and lipid properties,
combined with appropriate enzymic activities.
Wheat protein as a quality determinant.
The unique dough-forming properties of wheat flour are primarily due to
its protein constituents, especially the gluten proteins. Thus, protein
content is the most important compositional attribute determining wheat's
market value and processing quality. However, protein content is only one
of many 'windows' through which we can look at wheat quality. As a single
window, it provides an inadequate picture, but it can be augmented by knowledge
of the variety and growing conditions. Further windows must be opened to
predict processing quality, such as amino-acid content (indicative of feed
value), gluten content (better than total protein content), gliadin:glutenin
ratio (providing insight into gluten quality), and the size distribution
of the glutenin polymer chains (probably the best indicator of dough strength).
Statistical correlations between dough properties and glutenin alleles have
opened our eyes to important differences between the contributions of the
various subunits of glutenin, especially the HMW glutenin subunits. By incorporating
the pure polypeptides into dough to observe their contributions to function,
it recently has been possible to directly validate this statistically based
picture. This approach is now useful in predicting what might be the potential
contributions of novel genes for glutenin polypeptides if they were inserted
into wheat by transformation. So far, these new genes have involved glutenin
subunits of altered chain length or cysteine composition. In this way, a
new picture of the ideal gluten protein is being assembled.
Wheat gluten's unique properties permit many uses.
Wheat utilization is of considerable and growing interest. Today, many increasingly
realize that wheat and its constituents, including its gluten proteins,
can have new, nontraditional uses. Wheat is abundant, and new nonfood uses
and markets are needed badly. Gluten is unique, and its protein fractions
are complex materials. Glutenin is a polymeric gluten fraction with a molecular
weight in the millions, formed from smaller proteins. Gliadins are smaller
(~40,00060,000 MW) nonpolymeric proteins. Variation in gluten composition
among classes and cultivars greatly influences wheats properties and quality.
Gluten structure has been studied to explain its unique properties. HMW
glutenin subunits join end-to-end through disulfide bonds to provide a backbone
to the gluten complex. LMW-glutenin subunits also cross-link through disulfides
into the protein network. Smaller gliadin molecules are incorporated into
gluten primarily through hydrogen and hydrophobic bonds. When flour is hydrated
and mixed to form a dough, disulfide bonds rearrange as proteins align,
and gluten forms. The ultimate structure and properties of gluten thus depend
on amounts and types of specific proteins. Even slight changes in type or
amount of key subunits can markedly change glutens quality or functionality.
Foods and feeds always will be the most important use of wheats. Studies
25 to 50 years ago showed that films can be made from gluten proteins, and
that gluten can be modified in many ways to change its properties. Several
research groups are now developing gluten films, plastics, and polymers
and are investigating chemical and enzymatic modifications that can lead
to new products.
A rapid method for quantitation of insoluble polymeric proteins
in U.S. wheats: relationship to quality parameters.
The baking properties of several genotypes of U.S. hard wheats grown in
state nurseries for the Wheat Quality Council (WQC) were analyzed by the
Hard Winter Wheat Quality Laboratory. Flours (250 mg) from each individual
line and location were extracted three times with 50 % 1-propanol (1 ml)
for 5 min each. Samples were vortexed during extraction. This method was
effective in removing all monomeric proteins, because no detectable protein
was found in the third extract. Size exclusion chromatography (SEC) revealed
that some polymeric proteins were extracted with this procedure, as reported
for longer extraction times. The pellets were oven dried (130°C) for
1 h and analyzed for protein contents by a LECO Instruments (St. Joseph,
MI) thermogravimetric analysis system. The protein remaining in the pellet
consisted mainly of unextracted polymeric protein (UPP). The % UPP (pellet
protein/total flour protein) was correlated to various baking quality parameters,
with the highest correlation to bake mixing time. Linear correlation coefficient
(r) values for bake mix time to % UPP were 0.72 (p < 0.001, n = 46) for
the 1995 WQC set (winter wheat), 0.88 (p < 0.0001, n = 28) for the 1996
WQC set (winter wheat), and 0.71 (p < 0.0001, n = 24) for the 1996 WQC
set (spring wheat). This procedure is highly reproducible with a % RSD of
< 2 % within a given extraction set and a % RSD of < 5 % between extraction
sets. This technique is simple and rapid. Over 100 samples can be analyzed
easily per day.
Advances in cereal protein separation techniques.
The ability to separate and characterize cereal proteins has improved dramatically over the past 15 years. Analytical methods using proven separation technologies combined with computer control and analysis have provided unsurpassed resolution and information. Methods with the best resolution and highest sensitivity include: mass spectroscopy, laser light scattering, high-performance liquid chromatography, and high-performance capillary electrophoresis.
Cereal proteins: composition of their major fractions and methods
for identification.
Extraction conditions for separating the various protein fractions from
the five major cereal grains (wheat, rice, maize, barley, and oats) were
reviewed. Considerable variation in amount of solvent to solute and buffers
was noted. Results of the amino acid analyses of each protein fraction from
each cereal type also were compared, along with nutritional profiles. Electrophoretic
analysis methods, including A-PAGE, SDS-PAGE, IEF, and HPCE, for each of
those fractions were described. Considerable variation in methodology for
each fraction was found, but the results were similar. A complementary method,
HPLC, also was described, and some HPLC results were mentioned when it was
used together with an electrophoretic procedure. Prolamins and glutelins
make up the bulk of the proteins in all cereals, except for oats, where
the globulins play a larger role. The alcohol-soluble fraction (prolamin)
is normally the most useful for varietal identification. However, the large
numbers of closely related cultivars have led to the utilization of other
protein components. The only consistencies in the cereal analyses described
are that no one system or protein fraction has been found sufficient to
identify all varieties of any cereal species and that Coomassie blue dye
is used commonly for staining all the cereal protein bands.
Strategies for separation of wheat proteins by high performance capillary
electrophoresis.
Improved chemistries for separating wheat proteins by HPCE are described.
We previously reported separation of cereal proteins by free zone capillary
electrophoresis (FZCE) using pH 2.5 sodium phosphate buffers. To improve
separations, low conductivity buffers containing combinations of citric
acid, lactic acid, or phosphoric acid in conjunction with -alanine (replacing
monobasic sodium phosphate as the conjugate base) can be employed. These
buffers generate much lower currents during a separation and shorten analysis
times, although maintaining high resolution. Buffers containing citric acid
generally exhibited much higher theoretical plates per meter (~300,000400,000
N/m) and slightly faster analysis times than previously used buffer systems.
Gluten proteins can be separated by combining reversed-phase high performance
liquid chromatography (RP-HPLC) with FZCE. These 2-D separations provide
characterization of gliadin subclasses and of both HMW- and LMW-glutenin
subunits in the FZCE separations and provide high resolution separations
of both groups of proteins. Size-based separations also are possible using
replaceable sieving matrices. Polymers composed of dextran (10 %), pullulan
(7 %), and linear polyacrylamide (3 %) were tested for separating glutenin
subunits by size. Pullulan and dextran both yielded good separation of glutenins
in high ionic strength borate buffers. Several classes of additives including
organic solvents, sugars, salts, and zwitterions were tested for effects
on resolution, with different additives producing different selectivities
in the separations.
Influence of salts and aggregation of gluten proteins on reduction
and extraction of high-molecular-weight wheat glutenin subunits.
HMW-glutenin subunits of wheat were extracted by various combinations of
reducing agents, salt solutions, and solvents. Preferential extraction of
1D-encoded HMW-glutenins occurred when flours were extracted with TRIS-HCl-
SDS buffer at pH 6.8 containing 6 % mercaptoethanesulfonic acid (MESNA)
and analyzed by SDS-PAGE. Similar effects also were found when DTT or BME
were used in conjunction with nonchaotropic salts. If flours were extracted
first with 50 % 1-propanol, the extraction procedure yielded all HMW-glutenins,
even in the presence of MESNA or high levels of salt. Addition of alcohols
or chaotropes to the TRIS buffer solutions containing MESNA or of solutions
containing salt also extracted all HMW-glutenins.
Wheat lipids as a quality determinant.
Free lipids (FL) are minor components of wheat flour with major effects
on bread making. Fractionation and reconstitution studies revealed that
loaf volume and crumb grain were improved by polar lipids (PoL), especially
digalactosyldiglycerides (DGDG) among glycolipids (GL), but not by nonpolar
lipids (NL). With U.S., Canadian, or Greek wheats, varietal variations in
FL compositions (GL, NL/PoL, or NL/GL ratios) were correlated significantly
with bread loaf volume (LV), as reported by various researchers. The FL
content/composition of 12 commercial hard winter wheat cultivars grown in
six counties in Kansas were studied. Analysis of variance indicated that
the growing region (R), cultivars (C) and the 'C x R' interaction had significant
effects on FL contents/composition. Variations in NL were more influenced
by C than R or the 'C x R' interaction, although R had shown more significant
effects on GL and their fractions, monogalactosyldiglycerides (MGDG) and
DGDG. Phospholipid contents of FL were affected mostly by the 'C x R' interaction.
Free NL or FL contents had significant, negative, phenotypic correlations
with LV. Both DGDG contents and the NL/DGDG ratios had significant, genotypic
correlations with crumb grain scores. The MGDG contents had a significant
and negative phenotypic correlation with optimum bake water absorptions.
The NL/DGDG ratios and MGDG also had significant genotypic correlations
with bake mix times. However, they were only partially responsible for variations
in baking quality parameters. Thus, wheat lipids cannot be the sole quality
determinants, but good supplementary ones, especially for a wheat breeding
program.
Advances in lipid extraction and separation techniques.
Wheat free lipids (FL) are considered as important quality factors. The
analysis of flour FL is improved by recent advances in analytical techniques
including supercritical fluid extraction (SFE), solid phase extraction (SPE),
and HPLC with diode array detector (DAD) and evaporative light scattering
detector (ELSD). The SFE method is applied to extract flour FL replacing
Soxhlet extraction. The fractionation of flour FL is improved by SPE. Separation
and determination of FL classes, especially monogalactosyldiglyderide (MGDG)
and digalactosyidiglyceride (DGDG), by HPLC is also improved by the development
of detectors such as DAD and ELSD. These improvements in FL analysis are
expected to improve quality evaluation in the wheat breeding program or
industry.
Hard winter wheat flour free lipids: relationships with wheat/flour quality factors and variations.
The relationships between flour free lipids and wheat/flour quality factors and the effects of cultivar and region on the lipids were investigated using 12 hard winter wheat cultivars grown in six counties in Kansas. Monogalactosyldiglycerides (MGDG) had significantly negative genotypic and phenotypic correlations with near infrared hardness score and negative phenotypic correlations with single kernel hardness score. Glycolipids (GL), MGDG, and digalactosyldiglycerides (DGDG) showed significant genotypic correlation coefficients with gluten index. DGDG had significant phenotypic correlations with peak viscosity, time to peak, trough viscosity, and final viscosity among flour pasting properties. Mixograph and baking water absorptions showed significant negative correlations with total free lipids (FL), nonpolar lipids (NL), and the ratio of NL/DGDG. Mixograph and baking mixing times and mixograph mixing tolerance had significant negative genotypic relationships with the ratio of NL/DGDG. Crumb grain scores showed significant genotypic correlations with DGDG in a positive way and with the ratio of NL/DGDG in a negative way. Loaf volumes had significant phenotypic relationship with NL. Significant differences in cultivars, regions, and their interactions were recognized for FL, NL, GL, and MGDG. NL indicated a higher percent of total variance for cultivar effect than those associated with region or interaction effects. Among flour lipids, phospholipids showed significant difference in phenotypic stability between cultivars.
Light and electron microscopy of drying unripe wheat grains. The possible
role of endosperm cell senescence and its relationship to endosperm texture.
The HRWW Karl and SRWW Clark were field-grown during the 1996 growing
season and spikes were tagged at flowering. Entire wheat spikes were collected
at 21 days after flowering (DAF), placed in a 30°C oven and allowed
to dry for 0, 2, 4, 8, 12, 24, 48, and 96 h. At the appropriate times, grains
were removed from several spikes and prepared for light and transmission
electron microscopy. One-micrometer-thick plastic sections were cut with
glass knives and followed by ultra-thin sections cut with a diamond knife.
Little change was observed in the starchy endosperm until after about 8
h of drying, when the periphery of many of the large protein bodies found
in the subaleurone region started to become crenated. Also present throughout
the endosperm were small voids and small individual protein bodies. Twelve
hours of drying resulted in most of the large protein masses exhibiting
irregular edges, although small protein bodies still were observed in the
central endosperm regions of each cheek. Twenty four hours of drying converted
all of the protein bodies into a matrix, and individual protein bodies were
no longer observed in the starchy endosperm. The voids that were prominent
at earlier stages of drying were no longer present at 24 h.
Fate of dwarf bunt spores during cleaning and milling of wheat.
Wheat contaminated with teliospores of T. controversa was mixed
with uncontaminated wheat and processed through the Kansas State University
pilot mill. Two 50-bushel lots of the contaminated mixture were cleaned,
tempered, and milled. Approximately 500 samples of wheat, cleanings, and
mill fractions were collected and examined for the presence of intact and
broken spores. After whole wheat samples (50 g) were washed, sieved through
a 60-µm nylon sieve and centrifuged, the pellet was examined for the
presence of T. controversa spores. The procedure was modified as
needed to accommodate cleanings and mill fractions. Samples of whole wheat
decreased in spore contamination at each step in the handling process, and
large numbers of spores were found in materials that were sieved or aspirated
from the grain. Tilletia controversa spores are susceptible to cracking
and breaking from mechanical handling, but the proportion of broken spores
did not increase greatly in our tests. Very few spores were found in bran,
germ, and shorts; none were detected in red dog or straight-grade flour.
The results showed that a high percentage of spores can be removed from
wheat by mechanical cleaning, but removing all of them is not feasible.
Activities of the Hard Winter Wheat Quality Laboratory.
The Hard Winter Wheat Quality Laboratory (HWWQL), established in 1937
by an Act of Congress, coöperates with public (USDA-ARS and 16 state
Agricultural Experiment Stations) and private breeders in developing and
releasing HWWs with good grain characteristics and intrinsic end-use quality.
We evaluate approximately 3,000 HWW samples on a yearly basis. Quality testing
includes: physical and chemical grain characteristics; milling (75 g to
60 kg wheat) properties; mixing, gluten, and pasting characteristics; NIR
spectra data collection of all wheats, ground meals, and flours; and bread-making
quality evaluations. The HWWQL has a leading role for Hard Winter Wheat
Quality Council samples of new releases or wheat cultivars near release
by testing various quality evaluations, milling, and distributing flours
to the coöperating baking and milling industries and quality testing
labs. We bridge the quality parameters desired by industry to those being
pursued by wheat breeders. Our current research projects include: development
of baking methods including ultra-microbaking using 2- or 5-gram flours
and microbaking using 10-gram flour, which will highly correlate to pup
straight-dough method (100-gram flour) and pound sponge and dough method
(300-gram flour); rapid estimation of quality parameters of HWW breeding
lines based on NIR scanning spectra database (400-2,498 nm) of over 8,000
wheats and over 5,000 flours; studies on the biochemical relationship of
quality parameters including flour particle size and starch granular size
distribution on bread crumb grain, protein quality and quantity, and flour
lipid content and composition; and the genetic and environmental effects
on HWW quality and biochemical quality determinants.
Overview of U.S. wheat and flour quality.
The U.S. annual wheat production is about 62 million metric tons, and
one-half is exported to countries throughout the world. All exported U.S.
wheat is subject to USDA; Grain Inspection, Packers, and Stockyards Administration
(GIPSA); Federal Grain Inspection Service (FGIS) standards, which officially
certify the wheat grades and condition at export points. There are six defined
wheat classes (hard red winter, hard red spring, soft red winter, durum,
hard white, and soft white) and unclassified wheat. Minimum requirement
of test, maximum limits of damaged kernels, foreign material, shrunken and
broken kernels, defects, and containment of wheat of other classes determines
wheat grades within a given class. Differences between U.S. wheat classes
are generally use-oriented, and different wheat classes grow in different
regions. By Congressional mandate, four ARS Regional Wheat Quality Laboratories
(RWQL) were established for improvement of U.S. wheat quality based on their
end-uses by evaluating breeding lines. In 1936, the Soft Wheat Quality Laboratory
was established at Wooster, OH; in 1937, the Hard Winter Wheat Quality Laboratory
at Manhattan, KS; in 1946, the Western Wheat Quality Laboratory at Pullman,
WA; and in 1963, the Hard Red Spring and Durum Wheat Quality Laboratory
at Fargo, ND. All four RWQLs evaluate physical and chemical characteristics
of grains, experimental milling, flour quality, dough properties, and baking
or other end product processing quality parameters for cookies, cakes, breads,
spaghetti with durum wheat semolina, and/or noodles. Based on quality data
accumulated by the four RWQL during the past 30-60 years, quality-prediction
methods for functional properties have been developed and used to predict
certain end-use quality parameters by each lab. Recently, some testing methods
have been added or replaced: All four labs replaced the Kjeldahl Method
with the Leco N2 Analyzer and NIR Method; new use the USGMRL-developed Single
Kernel Characterization System for grain characteristics; and now use the
NIRSystem 6500 for chemical parameters of both wheats and flours and for
a complete spectral scanning of whole wheats, meals, and flours over 400-2,498
nm. With biochemical components responsible for certain functional properties
of end products and experimental processing data, we are working toward
developing a quality prediction system. The end-use quality estimation of
whole wheat kernels and a wheat marketing system based on end-use quality
are approaching.
Cultivar and environmental variations for hard winter wheat quality factors. I. Wheat characteristics and flour yields.
To investigate the effects of genotype and growing environment on wheat/flour
quality and the relationships of wheat characteristics with the end-use
properties, we used 12 HWW cultivars grown and harvested at six regions
in Kansas in 1993. Test weight showed significant phenotypic correlations
but insignificant genotypic correlations with wheat density and single kernel
weight (SK-WT). Significant phenotypic and genotypic correlations occurred
among wheat hardness parameters such as near infrared hardness score (NIR-HS),
single kernel hardness score (SK-HS), peak force (SK-PF), and SK-PF standard
deviation (SD) obtained by the Single Kernel Wheat Characterization System
(SKWCS). Wheat density also showed significant relationships with NIR-HS,
SK-HS, SK-PF, and SK-PF SD. Flour yield showed significant phenotypic correlation
coefficients with SK-PF (r = 0.52, P < 0.01), test weights (r = 0.50,
P < 0.01), NIR-HS (r = 0.50, P < 0.01), SK-HS (r = 0.43, P < 0.01),
SK-PF SD (r = 0.43, P < 0.01), SK-WT (r = 0.38, P < 0.01), wheat density
(r = 0.36, P < 0.01), and wheat ash contents (r = 0.35, P < 0.01),
suggesting the usefulness of SKWCS in evaluating the milling quality. According
to analysis of variance and variance component analysis, the environment
effect was dominant on wheat and milling characteristics, especially wheat
density. However, SK-HS SD, SK-WT, diameter (SK-DM), and SK-DM SD determined
by the SKWCS showed larger variance associated with cultivars than with
regions or interactions among cultivars and regions. Single kernel PF and
percent of large kernels showed significant differences in phenotypic stability
among cultivars, assessed by a nonparametric method; Newton had most stable
performance across the growing regions for SK-PF.
Cultivar and environmental variations for hard winter wheat quality
factors. II. Baking parameters and their relationships with wheat charactistics.
Twelve HWW cultivars harvested in six counties in Kansas were analyzed to
investigate the effects of cultivar genotype, region (environment), and
the 'G x E' interactions on baking parameters and their relationships with
wheat characteristics. Significant linear correlation coefficients (r) were
calculated between baking parameters. Bread loaf volume had significant
and positive phenotypic (r = 0.84, P < 0.01) and genotypic (r = 0.70,
P < 0.05) correlations with proof height. A significant, positive genotypic
correlation (r = 0.70, P < 0.05) occurred between loaf volume and loaf
volume regression (LVR). Baking parameters also were correlated significantly
with wheat characteristics. Bread loaf volume had significant, negative,
phenotypic and genotypic correlations with milling quality factors such
as single kernel peak force (SK-PF), percent large kernels, single kernel
weight (SK-WT), and near infrared and single kernel hardness scores. The
LVR had significant and negative genotypic correlations with percent large
kernels, SK-PF, and SK-WT. Analysis of variance (ANOVA) indicated that the
effects of genotype, environment, and the 'G x E' interaction on baking
parameters were significant for all baking parameters except crumb grain
score. Only the 'G x E' interaction had a significant effect on crumb grain
score. Variance component analysis indicated that environment influenced
flour protein contents, baking water absorptions, proof heights, and loaf
volumes more than genotype or the 'G x E' interaction. However, baking mixing
times and LVR were affected more by genotype than E or the 'G x E' interaction.
The 'G x E' interaction effect was dominant for crumb grain score as suggested
by ANOVA. No significant differences occurred among cultivars in phenotypic
stabilities for baking parameters.
Near infrared reflectance spectroscopy of flour-water doughs during mixing.
Numerous instruments have been developed to obtain objective data on the mixing properties of dough in order to predict their behavior in the bakery. Recording dough mixers such as the farinograph and the mixograph have long been used to visualize dough development and breakdown. Although these methods are effective in estimating such factors as optimum mixing time and water absorption, mixing tolerance, and protein quality, they fail to provide fundamental chemical information on the mixing properties of dough and basic dough constituents such as protein, starch, and lipid in the presence of water. In this study, near infrared reflectance (NIR) spectroscopy was utilized in the analysis of a flour-water dough system as the dough was mixed with a computerized mixograph. Real-time NIR spectral data were collected on doughs made with hard winter wheat flours obtained from federal regional performance nursery samples. Multivariate statistical techniques were applied to the NIR spectra, and correlations were found associating specific wavelengths to mixing quality parameters.
Comparison of pup straight-dough and pound sponge and dough breadmaking
procedures.
Two variations of the pup strength-dough (S-D) method (I proofing for
constant time and II proofing for constant height) were compared with the
pound sponge and dough (Sp&D) method to evaluate bread-making parameters
of 52 flours from the 1996 Wheat Quality Council hard wheat samples (28
winter and 24 spring wheats). The mean values between pup S-D and pound
Sp were, respectively, 68.2 versus 58.3 % for water absorptions (WA) and
5.1 versus 5.6 min for mix times (MT). Mean loaf volumes (LV) of 52 flours
were 923 cc by (I) and 940 cc by (II) with the pup S-D method and 2,459
cc by the pound Sp&D method. Mean crumb grain (CG) scores were 3.45,
3.87, and 3.94, respectively, for breads produced by pup S-D methods (I)
and (II) and the pound Sp&D method. Significant differences occurred
between the pup S-D and the pound Sp&D methods in WA, MT, LV, and CG
scores. Pup LV were not significantly different but CG scores were different
by methods (I) and (II). Bread CG scores were not significantly different
between pup S-D method (II) and pound Sp&D method using proofing to
constant height. Highly significant linear correlations occurred between
pup and pound bread-making parameters including WA (r = 0.92), MT (r = 0.76),
CG scores (r = 0.49 for I and 0.51 for II), and LV (r = 0.80 for I and 0.66
for II). Thus, evaluation of baking quality for wheat breeding lines by
the pup S-D method is a justifiable method. Some differences in quality
aspects between winter and spring wheats were related to mixograph parameters
and flour protein contents.
Starch properties in relation to bread crumb grain.
Crumb grain of sliced bread is one of the most important quality parameters in bread evaluation. To investigate the effects of starch on bread crumb grain, starches were isolated by a dough hand-washing method from 12 HWW flours with protein contents of 11.8-13.6 % (14% mb) that produced breads with pup loaf volumes of 910-1,035 cc and different crumb grain scores ranging from 1 (questionable to unsatisfactory) to 4 (satisfactory). The starches were studied for weight (wt) % of B-granules, starch damage, swelling power (92.5°C), amylose content, and granular size distribution by quantitative digital image analysis. No significant correlations occurred between crumb grain scores and most of the starch characteristics. However, the wt % of B-granule starch showed a significant (r = 0.672, P < 0.05) polynomial relationship with crumb grain scores. The best crumb grain scores were obtained when the flours had the wt % of B-granules from 19.8 to 22.5 %, whereas poor crumb grain scores were obtained when wt % of B-granules were either below 19.8 % or above 22.5 %.
Use of an autosampler for dynamic-headspace extraction of volatile compounds
from grains and effect of added water on extraction efficiency.
To improve convenience and consistency of results for routine detection
of volatile compounds associated with off-odors in wheat and other grains,
we used an autosampler (Archon from Varian Associates) attached to a purge
and trap instrument. The autosampler performed reliably during the analyses
of more than 500 samples. Trapped volatiles were transferred to a gas chromatograph-mass
spectroscopy instrument for separation and detection. Dynamic extraction
of volatiles from about 20 g of whole grain at 80°C was accomplished
by purging helium through a sample vial with a Teflon-lined septum on each
end. The autosampler also provided a means of adding an internal standard
to the sample before the purging began, which was a very useful feature.
The addition of water (at least 1 ml) required for proper transfer of standard
compound into the sample did not adversely affect extraction of most volatiles
from the grain, especially with starchy grains such as wheat. Extraction
of some aldehydes, alcohols, and esters from all grains were enhanced slightly
by addition of water.
Volatiles extracted from whole and ground wheat samples by supercritical
carbon dioxide and direct helium purge.
Volatiles were extracted from whole and ground wheat at 50°C with
supercritical carbon dioxide (SC-CO2) at 17.3 -41.4 MPa. Loss of volatiles
was avoided by directing a slow flow of the SC-CO2 extract into a collection
tube held at - 78°C. The cold collection tube was mounted immediately
on a purge and trap instrument for transfer of volatiles to a gas chromatograph
equipped with infrared and mass spectrometric detectors. When compared with
conventional purge and trap procedures that involve purging the grain directly
with helium, the SC-CO2 procedure more effectively extracted most volatiles
from wheat samples, especially acids, aldehydes, and other compounds with
polar functional groups. Direct helium purge procedures are faster, more
convenient, and possibly better for detecting some highly volatile compounds.
High SC-CO2 pressures reduced the amounts of most volatiles detected by
the chromatography system. In general, ground samples yielded higher amounts
of volatiles than whole grains. However, a few compounds were relatively
more prevalent in whole grain, possibly because those compounds were present
on or near the surface of the grain. Both volatile-collection procedures
are being used to investigate differences in volatiles among wheat cultivars
with normal odors and to identify compounds associated with off-odors in
wheat samples.
Sensory properties of musty compounds in food.
Musty aroma and flavor are a major problems in a variety of foods and
packaging materials. Some compounds such as geosmin and 2-methylisoborneol
have been studied in relation to water, grains, fish, and potatoes, but
a variety of other compounds can result in mustiness. Thirty-four chemical
compounds, including chloroanisoles, pyrazines, and aldehydes, potentially
related to mustiness in foods or packaging were tested in this study. Six
highly trained sensory panelists smelled each compound dissolved in propylene
glycol (if soluble) at dilutions of 1,000, 5,000, and 10,000 ppm, although
some were tested at levels as low as 100 ppm or as high as 100,000 ppm.
A range of musty-type odors including earthy, moldy, fungal, damp basement-like,
mushroomy, and fermented were found in at least some of the compounds. As
expected, changes in concentration or slight modifications in functional
groups resulted in large differences in character.
Sensory characteristics of chemical compounds potentially associated
with smoky aroma in foods.
Smoky aroma can either enhance foods (e.g., meat or cheese) or be detrimental
to the product (e.g., raw or processed grains and grain products). Twenty-one
chemical compounds suggested from the literature or from gas chromatography
headspace analysis of raw grains as potentially responsible for smoky aroma
were studied. Five highly trained sensory panelists smelled each compound
dissolved in propylene glycol (if soluble) at a dilution of 5,000 to 20,000
ppm depending on the strength of the compound. Approximately 60 % of the
compounds were found to have some smoky character, although the intensity
of smokiness often was low. Some compounds such as benzyl disulfide and
3,7-dimethyl-6-octenoic acid were predominately smoky, but had other aroma
characteristics that were lower in intensity. Most compounds had other aroma
characteristics that were more intense than smoky (e.g., 2-ethylpyridine)
and some compounds, such as 1-methylpyrrole, were not smoky at all.
Development of a grain odor sampler.
Grain odor is a characteristic that is evaluated during the process of grain grading. A grain inspector is required to determine if any undesirable odor is present by immersing the nose in the grain surface and sniffing around the sample. This sniffing procedure raises concern for the workers' health as affected by inhaling grain dust particles or mold spores that frequently are present in grain samples. Grain graders need an odor evaluation method that minimizes exposure to airborne particles without affecting odor evaluation. Researchers at the Grain Marketing and Production Research Laboratory designed and fabricated prototype grain odor samplers to aid grain inspectors and reduce risk. The odor sampler was tested for particle emission characteristics to establish a recommended operating procedure. Odor evaluation integrity was examined by GMPRC scientists before delivery of and testing by the Federal Grain Inspection Service, which determined the response of field grain graders to the new method. A bench model, timed-airflow system for grain odor testing was developed through the FGIS responses from experimental prototypes.
Mixograph instrumentation.
A 10-gram mixograph was modified and instrumented to facilitate digital
acquisition of flour-dough mixing data. The instrumentation methods provided
the following capabilities: acquisition of mixing bowl torque synchronized
with moving pin location, variable mixing speed with forward or reverse
mixing action, bowl rotation to fixed angular positions, bowl torque calibration,
and methods for system standardization. Repeatability and methods of standardization
were studied as were the effects of absorption, temperature, mixing speed,
mixing-pin height, dough load and bowl position. Sensing moving pin location
by means of an encoder allowed collection of bowl torque at specific moving
pin locations and observation of mixogram cycles as the moving pins either
'hurdled' or 'straddled' the stationary bowl pins during flour-dough mixing.
Goals included objective interpretation of mixogram characteristics and
identification of flour-dough properties generally not observed in conventional
digitized mixograph operations.
Digitization of interpretive line slides for development of a visual grain-grading knowledge base.
Computer-aided grain grading is becoming possible with the increase in performance of the PC. To incorporate the standards set by the Federal Grain Inspection Service, the interpretive line slides, which are the standards, were digitized into machine-readable images for the purpose of extraction of machine-recognizable characteristics. These characteristics will be the bases of automated grain grading systems. Accurate digitization and color reproduction are essential for success. Problems were encountered and overcome to produce an acceptable image base for development of a visual grain grading knowledge base.
Instrumentation for spatial visual-spectral characterization.
The ability to detect grain damage using specific wavelength data in relation
to spatial coordinates is needed for development of automated grain-grading
systems. An instrument was developed to determine wavelength-specific data
(visible spectrum) synchronize with x-y coördinate viewing positions.
The wavelength range was 400-650 nm with a 5 nm bandwidth and the maximum
viewing area was '0.8 x 0.8 mm'. The potential of the instrument developed
was evaluated by examining the differences detected between blue eye mold
and purple plumule in corn. The instrumentation and methodology can be used
to develop the spectral database necessary for design, development and implementation
of machine vision-based grain-grading systems.
The single kernel characterization system.
Wheat hardness is a characteristic that influences end-use processing.
Soft wheat is milled differently from hard wheat and produces flour particles
that can plug the sieves on a hard wheat flour mill. Mixtures of soft and
hard wheat kernels are undesirable in the marketing channel. Hardness is
set by plant genetics, but the growing environment can influence kernel
morphology variations expressed by varieties. Technology for rapidly determining
single kernel hardness was developed to objectively classify commercial
wheat as hard, soft, or mixed. Objective wheat classification technology
was initiated by development of rapid single-seed handling techniques and
instrumented systems to facilitate high-speed data acquisition for hardness,
moisture, size, and weight measurements. Software for data processing was
developed through extensive evaluation of experimental prototypes. Through
a Cooperative Research and Development Agreement with Perten Instruments
of North America, the technology was transferred to commercial production
of the Single Kernel Characterization System (SKCS) 4100. The SKCS 4100
has applications that go beyond wheat classification. Break release distribution,
an important factor in mill control, has been shown to be related significantly
to measurements of single kernel physical properties. Other work has shown
that the SKCS can be used to measure important physical properties in grain
sorghum and barley.
Automated quality measurement of single wheat kernel using near-infrared reflectance and the single kernel characterization system.
An automated system for measuring protein, moisture, color class, scab,
bunt, and hidden insect infestations of single wheat kernels was developed
by integrating a single kernel characterization system (SKCS) with a near-infrared
diode array spectrometer (DAS). The SKCS and DAS (Perten Instruments) were
integrated via fiber optics and analyzes one kernel per 4 seconds using
the 400-1,700 nm wavelength range. Partial least squares regression was
used for all analysis and calibrations. Specific wavelength regions contributing
to correct classifications were identified. The accuracy and precision achieved
compare favorably with those of bulk sample instruments. Protein was predicted
with a SE = 0.75 and r2 = 0.94. Moisture content was predicted with an SE
= 0.31 and r2 = 0.96. Color class was predicted with an r2 = 0.83 and correct
classification rate of 99.2 %. Hidden insect infestation was predicted with
an r2 = 0.70 and with 99.1 % of kernels with 2nd instar or larger larva
detected. Over 90 % of kernels affected by scab and bunt were detected.
Micropycnometer measurement of single-kernel density of healthy, sprouted, and scab-damaged wheats.
Samples from four market lots of HRWW and SRWW wheat containing sprout-
and scab-damaged kernels were used to test a prototype single-kernel density
micropycnometer. Fifteen kernels for each damage type and an equal number
of healthy kernels were weighed to the nearest 0.01 mg, then measured for
volume to the nearest 1.0 µl. Volume measurements for all kernels
were performed three consecutive times with the micropycnometer, then kernels
were evaluated for weight, size, moisture, and hardness using a Perten Instruments
4100 Single Kernel Characterization System. The structure of the sampling
plan and the goals of the study indicated that a mixed-model statistical
analysis was needed. The fixed effects were wheat class and type of kernel,
and the random effects included lot, the interaction of lot with class and
kernel type, kernels within each lot, and repeated measures of single-kernel
density. Study results indicated that variability of the three measurements
per kernel did not depend on type of kernel or class of wheat. The standard
deviation for repeated density measurements was 0.0029 g/cc. Type of kernel
significantly affected mean density; healthy kernels averaged 1.28 g/cc,
sprout-damaged kernels averaged 1.19 g/cc, and scab-damaged kernels averaged
1.08 g/cc. Wheat class did not exert a significant influence on single-kernel
density.
Development of an experimental roller mill.
Traditional experimental roller mills have limitations, especially in
the measurement of power and energy requirements when milling different
wheat varieties at different treatments. We have designed and an experimental
two-roll mill for high speed data acquisition. The rolls used are 250 mm
in diameter and 100 mm in length with 0.5 teeth per mm and spiral of 1 mm
per 24 mm. Other roll configurations can be tested as studies progress.
The major operational parameters, such as feed rate, fast roll speed, slow
roll speed, and roll gap, can be adjusted accurately to fulfill various
testing requirements. The feed rate is controlled by a vibrating feeder
at rates from 2 to 40 kg/min per meter of roll length. Roll speeds can be
varied from less than 100 rpm to over 800 rpm using adjustable frequency
AC motor controllers. The data acquisition system records outputs from two
torque sensors, two rpm sensors, and the digital balance weighing the ground
wheat. From the collected data, fast roll power and energy, slow roll power
and energy, and the net power and energy can be obtained. Electrical noise
from motors and AC motor controllers is controlled by grounding, shielding,
and filtering. Results of several milling tests show this experimental roller
mill to be useful in studying effects of milling parameters and wheat physical
properties on energy requirements during first break grinding.
Energy requirements for size reduction of wheat-first break milling.
An experimental roller mill was fitted with instrumentation for computerized
data acquisition to facilitate the study of energy requirements for grinding
wheat in the 1 BK stage of the milling process. Milling tests were conducted
using three classes of wheats. Physical properties (test weight, thousand
kernel weight, true density, mean kernel size, single kernel characteristics,
NIR hardness, and moisture of the wheat samples) were determined prior to
milling. Six independent variables (class of wheat, moisture content, feed
rate, fast roll speed, roll peripheral speed differential, and roll gap)
each were used at three levels in the study. Two covariates, single-kernel
hardness and single-kernel weight, also were included in the statistical
analysis of the data. Prediction models were constructed for five dependent
variables, fast roll power, slow roll power, net power, energy per unit
mass and specific energy. The power and energy requirements for size reduction
in 1 BK milling of wheat correlated highly with the single kernel characteristics
of wheat samples. Feed rate significantly affected fast roll power, slow
roll power and net power. Roll gap had a significant effect on all dependent
variables studied. Effects of factors such as moisture, fast roll speed,
and roll peripheral speed differential on characteristics of the ground
materials and power and energy requirements were relatively small. However,
analysis indicated that interaction among these factors had significant
influence on roller mill grinding. The prediction models were found to be
robust by conducting verification tests on 10 samples of wheat of different
class and physical properties.
The determination of color class of single wheat kernels using
visible and near-infrared reflectance.
Wheat kernel color is an important quality factor to world markets, end
use, and wheat breeding. Kernel color serves as the basis of wheat segregation
in many countries. Traditional methods of wheat color measurement include
objective methods such as a sodium hydroxide solution method, phenol test
method, Hunter color difference meter, and a subjective method in which
the color is determined by a person(s) experience. The traditional objective
methods are time-consuming and tedious. For the subjective method, Federal
Grain Inspection Service personnel visually examine wheat samples to determine
kernel color. Variations in color determinations between inspectors can
result. Thus, a rapid and precise method to determine wheat color is needed.
The objective of this research is to develop a rapid, precise and nondestructive
method for wheat color classification. Near-infrared reflectance spectroscopy
is an alternative method which meets those requirements. An optical radiation
measurement system, which measured spectral reflectance from 400-2,000 nm,
was used to identify color class of single wheat kernels. Six classes of
wheat were used. Partial least squares and multiple linear regression analysis
were used to develop models for identifying red and white classes and difficult-to-classify
cultivars, which include red wheat that appears white and white wheat that
appears red. Results indicate that the 500-750 nm region can be used to
identify obviously red and white wheats with an accuracy of greater than
99 %. The 500-1,700 nm region can be used to identify difficult-to-classify
kernels with an accuracy of greater than 94 %.
Automated color classification of single wheat kernels using visible and near-infrared reflectance.
Modification of an existing single kernel wheat characterization system
allowed collection of visible and near-infrared (NIR) reflectance spectra
(450-1,688 nm) at a rate of one kernel per 4 seconds. The spectral information
was used to classify red and white wheats in an attempt to remove subjectivity
from class determinations. Calibration, validation, and prediction results
showed that calibrations derived from the full wavelength profile correctly
classed more kernels than either the visible region (450-700 nm) or the
NIR region (700-1,688 nm). Most results showed greater than 99 % correct
classification for single kernels when using the visible and NIR regions.
Averaging of single kernel classifications resulted in 100 percent correct
classification of bulk samples.
Effect of wheat kernel size and orientation on visible and near-infrared
reflectance spectra and color classification of single wheat kernels.
An optical radiation measurement system was used to measure reflectance
spectra of single wheat kernels from 400 to 2,000 nm. Six classes of wheat
were used for this study. Three kernel sizes (large, medium, and small)
and three orientations (crease side, 90 degrees, and dorsal side) were used
to determine how wheat kernel size and orientation affect the visible and
near-infrared (NIR) reflectance spectra and color classification of single
wheat kernels. The results showed that wheat kernel size and orientation
significantly affected visible and NIR reflectance spectral measurement
when the distance between a reflectance surface and the end of an optical
fiber was kept constant. The amount of radiation reflected by wheat kernels
increased as kernel size increased. The predicted values of red and white
kernels decreased as kernel size decreased. Kernel color varied with kernel
orientation. The dorsal size had more effect on the wheat color classification
than the crease side and side view. Some data pretreatments such as Multiplicative
Scatter Correction (MSC), first and second derivative, first derivative
with MSC, and second derivative with MSC could be used to reduce the effects
of kernel size and orientation on the reflectance spectral data. The wavelengths
with significant effects on spectral data also were found. Size-term multiple
linear regression models showed a strong correlation between kernel weight
and absorbance in the NIR region with an r2 from 0.70-0.92.
Effect of NaOH on visible wavelength spectra of single wheat kernels
and color classification efficiency.
A diode array system, which measures spectral reflectance from 400-700 nm,
was used to quantify the color of single wheat kernels before and after
soaking in NaOH as a means of determining color class. Wheat color classification
is currently a subjective determination and important in determining the
end use of the wheat. Soaking kernels in NaOH and classifying the soaked
kernels with the diode array system resulted in more difficult-to-classify
kernels being classified correctly (98.1 %) than with the visual method
of classifying kernels (74.8 %). Kernel orientation had a slight effect
on correct classification, with the side view correctly classifying more
kernels than the dorsal or crease view. The diode array system provides
a means of quantifying kernel color and eliminates inspector subjectivity
when determining color class.
Detection of insects in bulk wheat samples with machine vision.
Digital-imaging techniques were used to identify insect body parts of the adult lesser grain borer beetles, Rhyzopertha dominica, in bulk wheat samples. The samples contained dockage (weed seeds and damaged wheat kernels), which made the identification of insects more difficult. Multispectral analysis (red, green, and blue) was used in combination with pattern recognition techniques. Experiments were done with a subimage size (8 x 8 pixels) to identify insects. Statistical multivariate analysis and structural patterns were used for finding insects. The position of the insect (ventral, dorsal, and side) and particles clinging to the insect affected recognition success. Recognition success of R. dominica adults, some grass seeds, and other nonwheat components was higher than 90 %.
Detection of hidden insects in grain by automated NIR-reflectance spectrophotometry.
Key components of insect management in stored grain will be sophisticated
sampling techniques for determining the presence and extent of insect infestations
in a given commodity. Sampling for insects such as weevils and borers in
whole grain is complicated by the presence of hidden immature stages (eggs,
larvae, and pupae) inside kernels. Samples of grain may appear to be insect-free
if no adults are present, when in fact they could be infested heavily. For
this reason, new detection methods are needed. Ideally, the method should
be simple and fit into the current grading process. We investigated the
potential of a near-infrared spectrometer integrated with the single kernel
wheat characterization system to automatically and rapidly detect hidden
insects in wheat kernels. In this automated system, kernels infested with
larvae and pupae of three major insect pests were detected easily. This
system can be incorporated readily into the current inspection process.
In addition, the system can provide the wheat industry simultaneously with
automated information on hardness, protein content, moisture content, and
wheat color class and critical information necessary to monitor and manage
insect infestations in wheat.
Use of near-infrared reflectance (NIR) spectroscopy for detecting, identifying, and killing insects.
We could differentiate uninfested wheat kernels from those infested with
Angoumois grain moth, lesser grain borer, and rice weevil larvae using NIR.
Rice weevil and granary weevil adults were differentiated with 100 % accuracy.
Complete mortality of rice weevils was achieved with 90 seconds exposure
to NIR.
Automated nondestructive detection of internal insect infestation of wheat kernels using near-infrared reflectance spectroscopy.
Wheat kernels infested internally with larvae of three primary insect pests of grain, the rice weevil, Sitophilus oryzae (L.); the lesser grain borer, Rhyzopertha dominica (F.); and the Angoumois grain moth, Sitotroga cerealella (Olivier), were scanned with a near-infrared spectrometer incorporated into a single kernel characterization system (SKCS) to determine differences in absorption due to the presence of larvae. The SKCS delivers kernels into the spectrometer viewing area at the rate of one per 4 seconds. We detected kernels infested with larvae of all three species using this automated system. Moisture content, protein content, or wheat class did not affect classification accuracy. The calibration included spectral characteristics in the wavelength ranges of 1,000-1,350 and 1,500-1,680 nm. Larval size was a factor in the sensitivity of the system, with third and fourth instar rice weevil larvae being detected with 95 % confidence. In contrast to many other procedures used to detect internal insect infestations in grain, this system could be incorporated into the current grain inspection process and provide the grain industry with quantitative data on internal insect infestations in wheat.
Predicting insect density from probe trap catch in farm-stored wheat.
Insect monitoring is important in determining whether insect control is
needed and whether pest control was effective. Traps are often easier to
use than other methods of estimating insect density. However, the seasonal
changes in temperature and other factors can influence trap catch more than
the density estimates made with other methods, and methods must be developed
for converting trap catch to insect density per volume of grain. We investigated
the influence of the seasonal changes in grain temperature in two bins of
stored wheat on each of two farms in Kansas on the prediction of insect
density from probe trap catch. Estimates of insect density based upon the
numbers of adult insects caught using probe traps differed from those based
upon the number of insects found in grain samples. The numbers of insects
captured in traps decreased as grain temperature decreased during the storage
period, even though grain samples indicated that insect populations were
still growing. Thus, trap catches did not estimate insect population density
consistently throughout the storage period. Therefore, the insect density
in grain samples should be estimated from trap catch using the equations
that we developed to adjust for the effects of temperature on trap catch.
These methods will make probe traps more useful as monitoring tools for
stored-grain insect management programs.
Area-wide integrated pest management (IPM) for suppression of insect
pests in stored wheat.
A 5-year area-wide IPM project was funded recently by ARS to determine whether
more uniform application of insect pest management across the marketing
system could reduce insect problems in stored wheat. Insects are moved along
with grain from one elevator to another. If not controlled, insect problems
can be spread from one elevator to another. The first year of the project
will be for planning. The project is a collaboration of USDA-ARS, Grain
Marketing and Production Research Center, Kansas State University and Oklahoma
State University. The objective of the Area-Wide IPM project is to implement
a state-of-the-art stored-wheat IPM program in elevator networks in Kansas
and Oklahoma. The program will emphasize reducing the frequency of pesticide
use, the cost of pest management, and the risk of insect problems. Methods
to meet these objectives are intensive insect monitoring, computer models
predicting insect population growth and when insect control is needed, sanitation,
and early aeration to cool grain and reduce growth of insect and mold populations.
Wheat should be fumigated only when biologically and physically based methods
fail to keep insects below economically damaging levels. Recent changes
in grain marketing practices may have changed pest management needs. The
project will determine whether current pest management programs are the
most cost effective in reducing the risk of insect infestation.
News from the Grain Marketing and Production Research Center, Manhattan, KS.
Successful International Wheat Quality Symposium. The International Wheat Quality Symposium held in Manhattan, KS, in May attracted over 300 participants representing 32 different countries. Attendees heard presentations from leading research scientists in wheat quality and spent four days discussing wheat quality issues. Proceedings of the Symposium may be purchased from the Grain Industry Alliance, 200 Research Drive, P.O. Box 727, Manhattan, KS 66505, at a cost of $50 each.
Personnel changes. Dr. Jim Throne, research entomologist, was selected as the new Research Leader for the Biological Research Unit. Dr. Throne has been with ARS for approximately 18 years and has been a part of the Manhattan Biological Research Unit since 1994. He replaced Dr. Bill McGaughey who retired in July. The Biological Research Unit is responsible for developing and evaluating alternative methods of postharvest insect control to decrease the use of chemical pesticides and fumigants.
New Funding for the Plant Science and Entomology Research Unit (PSERU). The PSERU received an additional $500,000 in permanent funding beginning in the current fiscal year. These funds are being used to staff a new position in molecular genetics. The person hired to fill this position will be responsible for the development of germplasm that is resistant to karnal bunt and other emerging diseases for HWW. In addition, Dr. Jim Hatchett has retired after working for the Agricultural Research Service for over 36 years. Much of his effort was spent in studying and developing control methods for the Hessian fly. Dr. Hatchett will continue to test wheat cultivar resistance to this important pest on a part-time basis, and recruitment for a replacement to continue with this program is in process.
ARS Area-Wide IPM grant update. Development and implementation of an Area-Wide Integrated Pest Management Program in wheat, which was funded by a $2.7 million grant in 1997, is on schedule. Two elevator networks (one in Oklahoma and one in Kansas) have been selected to implement this program. Each of the networks contains several local elevators and a terminal elevator. The Kansas network also includes a flour mill. Work during the first year will include evaluation of the wheat quality contained in these networks along with the development of IPM-based insect control methods.
International activities. Dr. Okkyung Kim Chung, Research Leader
of the Grain Quality and Structure Research Unit will Co-Chair an American
Association of Cereal Chemists (AACC) Symposium on 'Grain Quality' in Moscow,
Russia, on 4-8 May, 1998. As the 1998 President of AACC and the U.S. Delegate
to the International Association for Cereal Science and Technology (ICC),
she also will serve as the AACC and USA representative to a symposium on
the "Genetic Engineering in Cereals" held in Vienna, Austria,
on 9-12 May. In 13-17 September, Dr. Chung will preside over the annual
meeting of the AACC that will be held in Minneapolis, MN. Dr. George Lookhart,
Research Chemist in this Unit, is the Program Chair for this meeting.
Publications.
Bean SR, Akkina SK, Lyne RK, Chung OK, Tilley KA, and Lookhart GL. 1997.
Quantitation of polymeric proteins in U.S. wheats: relationship to quality
parameters. Cereal Foods World Abstr 42:633.
Bean SR, Akkina SK, Lyne RK, Lookhart GL, and Chung OK. 1997. Relationships of various protein fractions with wheat baking quality. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p. 501. (Abstract)
Bean SR, Akkina SK, Lyne RK, and Lookhart GL. 1997. Capillary electrophoresis of wheat proteins. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p. 501. (Abstract)
Bean SR and Lookhart GL. 1997. 2-D separations of cereal proteins - HPLC and HPCE differentiation of cultivars and protein fractions. Cereal Chem 74:758-765.
Bean SR and Lookhart GL. 1997. Influence of salts and aggregation of gluten proteins on reduction and extraction of high molecular weight wheat glutenin subunits. Cereal Chem (In press).
Bean SR and Lookhart GL. 1997. Capillary electrophoresis of wheat proteins: separation of gliadins and glutenins by a novel two-dimensional technique, reversed phase high performance liquid chromatography combined with free zone capillary electrophoresis. Cereal Foods World Abstr 42:603.
Bean SR and Lookhart GL. 1997. Strategies for separation of wheat proteins
by high-performance capillary electrophoresis. Cereal Foods World Abstr
42:603-604.
Bechtel DB and Wilson JD. 1997. Ultrastructure of developing hard and soft
red winter wheats after air- and freeze-drying. Cereal Chem 74:235-241.
Caley MS, Chung OK, Liu X, Haden ZL, and Ohm JB. 1997. Comparison of pup straight-dough and pound sponge and dough breadmaking procedures. Cereal Foods World Abstr 42:614-615.
Chang CS and Steele JL. 1997. Performance characteristics of the inlet
section of a screw conveyor. Appl Engin Agric 13:627-630.
Chung OK. 1997. Overview of U.S. wheat and flour quality. In: Second
Inter Conf The Current Status of Flour-Milling and Cereals Production-Prospects
for Development, 2-6 June, 1997, Moscow, Russia. p. 10. (abstract)
Chung OK. 1997. Functional properties of wheat flour components and basic ingredients in breadmaking. In: Proc 14th SAAFoST Inter Congress Exhibit, Harnessing Food Sci and Technol for Sustainable Development, 1-4 September, 1997, Pretoria, South Africa. p. 72. (abstract).
Chung OK. 1997. Environmental safety concerns: changes in cereal testing and production quality evaluation methodologies. In: Proc 14th SAAFoST Inter Congress Exhibit, Harnessing Food Sci and Technol for Sustainable Development, 1-4 September, 1997, Pretoria, South Africa. p. 102. (abstract).
Chung OK. 1997. Greetings from the AACC: activities of the AACC. In:
Program Book Inter Symp on New Approaches to Functional Cereals and Oils,
Exhibition and Posters. Chinese Cereals and Oils Association (CCOA) Beijing,
China. pp. 3-5.
Chung OK. 1997. Comparison of conventional and modern cereal testing techniques.
ICC Jubilee Conf Proc, 11-13 June, 1997. Detmold, Germany. (abstract)
Chung OK. 1997. Overview of wheat and flour quality testing for the U.S. wheat breeding program. In: Proc Inter Symp on New Approaches to Functional Cereals and Oils, Exhibition and Posters. Chinese Cereals and Oils Association (CCOA) Beijing, China. pp. 559-564.
Chung OK. 1997. Environmental safety concerns: changes in cereal testing and product quality evaluation methodologies. In: Electronic Proc (Internet) 14th SAAFoST Inter Congress and Exhibit Harnessing Food Science Technology for Sustainable Development, Pretoria, South Africa (In press).
Chung OK, Downing JM, Hubbard JD, and Ohm JB. 1997. Varietal and environmental variations for hard winter wheat lipids. Cereal Foods World Abstr 42:628-629.
Chung OK, Hubbard JD, Downing JM, Ohm JB, and Burden CW Jr. 1997. Extraction methods for sunflower seed oil: Soxhlet vs supercritical fluid extraction. Cereal Foods World Abstr 42:628.
Chung OK, Hubbard JD, Downing JM, and Ohm JB. 1997. New extraction and fractionation methods for wheat flour lipids. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p 502. (Abstract)
Chung OK, Lookhart GL, Steele JL, Bean SR, Zayas IY, Martin CR, Ohm JB, Bechtel DB, Seitz LM, Wilson JD, Hubbard JD, Downing JM, Chang CS, Hagstrum DW, Kramer KJ, Sauer DB, Jun WJ, Park HS, Park SH, Baker JE, Flinn PW, Morgan TD, McGaughey WH, Seabourn BW, Kim YS, Shogren MD, and Koeltzow DE. 1997. Wheat research in the U.S. Grain Marketing Research Laboratory. Ann Wheat Newslet 43:282-296.
Chung OK and Ohm JB. 1997. Advances in lipid extraction and separation techniques. In: Proc Inter Symp on New Approaches to Functional Cereals and Oils, Exhibition and Posters. Chinese Cereals and Oils Association (CCOA). Beijing, China. pp. 504-508.
Chung OK and Ohm JB. 1997. Wheat lipids as a quality determinant. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. pp. 83-100.
Chung OK and Ohm JB. 1997. Cereal lipids. In: Handbook of Cereal Science and Technology (Kulp K and Ponte JG Jr eds), 2nd edition. Marcel Dekker Inc: New York, NY (In press).
Chung OK and Park SH. 1997. Functional properties of wheat flour components
and basic ingredients in breadmaking. In: Electronic Proc (Internet)
14th SAAFoST Inter Congress and Exhibit Harnessing Food Sci Technol for
Sustainable Development, Pretoria, South Africa. (In press).
Chung OK and Pomeranz Y. 1997. Cereal processing. In: Food Proteins:
Properties and Applications (Nakai S and Modler HW eds). VCH Publishers:
New York, NY. Vol. II (In press).
Chung OK, Seabourn BW, Caley MS, Fay KT, Lyne RK, Liu X, Haden ZL, and
Xiao ZS. 1997. Activities of the USDA/ARS Regional Wheat Quality Laboratories.
II. Hard Winter Wheat Quality Laboratory. In: Proc Inter Wheat Quality
Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS.
p. 498. (Abstract)
Chung OK and Steele JL. 1997. Closing remarks. In: Proc Inter Wheat
Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan,
KS. pp. 521-522.
Delwiche SR, Chung OK, and Seabourn BW. 1997. Protein content of hard red winter wheat by near-infrared spectroscopy on whole grain: collaborative study. J AOAC Inter. (In press).
Dempster RE and Steele JL. 1997. Digitization of interpretive line slides for development of a visual grain grading knowledge base. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p. 503. (Abstract)
Dempster RE, Steele JL, and Day D. 1997. Instrumentation for spatial visual-spectral characterization. ASAE Conf, St. Joseph, MO, 112 April, 1997. ASAE Paper No. MC97-126.
Dowell FE. 1997. Effect of NaOH on visible wavelength spectra of single wheat kernels and color classification efficiency. Cereal Chem 74:1-5.
Dowell FE. 1997. Automated color classification of single wheat kernels using visible and near-infrared reflectance. Cereal Chem (In press).
Dowell FE, Martin CR, Steele JL, and Wang, D. 1997. Automated measurement of single wheat kernel protein, moisture and color class using near-infrared reflectance. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p. 503. (Abstract)
Dowell FE, Steele JL, Martin CR, Throne JE, Baker JE, and Delwiche SR. 1997. Automated single wheat kernel quality measurement using near-infrared reflectance and the single kernel characterization system. Cereal Foods World Abstr 42:368.
Dowell FE, Steele JL, Wang D, Baker JE, Throne JE, and Delwiche SR. 1997. Automated single wheat kernel quality measurement using near-infrared reflectance. ASAE Ann Inter Mtg, Paper No. 97-3022.
Dowell FE, Throne JE, and Baker JE. 1997. Detection of hidden insects
in grain by automated NIR reflectance spectrophotometry. In: Proc
1997 Annual Inter Res Conf on Methyl Bromide Alternatives and Emissions
Reductions, 3-5 November, 1997, San Diego, CA. pp. 108-1 and 108-2.
Flinn PW and Hagstrum DW. 1997. Simulation of the effects of latitude, bin
size, and aeration on insect populations in stored wheat. J Econ Entomol
90:646-651.
Flinn PW and Hagstrum DW. 1997. Distribution of Cryptolestes ferrugineus (Coleoptera: Cucujidae) in response to temperature gradients in stored wheat. J Stored Prod Res (In press).
Hagstrum, DW, Flinn PW, and Gaffney J. 1997. Temperature gradient on Tribolium castaneum (Coleoptera: Tenebrionidae) adult dispersal in stored wheat. Environ Entomol (In press).
Hagstrum DW, Subramanyam Bh, and Flinn PW. 1997. Nonlinearity of a generic variance-mean equation for stored grain insect sampling data. Environ Entomol (In press).
Haque E, Reddy PV, Spillman CK, Fang Q, and Steele JL. 1997. Energy requirements for size reduction of wheat-first break milling. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p. 507. (Abstract)
Hazelton JL, Chung OK, Eastman JJ, Lang CE, McCluskey PJ, Miller RA, Shipman MA, and Walter CE. 1997. Regression equation for predicting absorption for 2-g direct drive mixograph. Cereal Chem 74:400-402.
Hickling R, Wei W, and Hagstrum DW. 1997. Studies of sound transmission in various types of stored grain for acoustic detection of insects. Appl Acoustics 50:263-278.
Huebner FR, Nelson TC, Chung OK, and Bietz JA. 1997. Protein distributions among hard red winter wheat varieties as related to environment and baking quality. Cereal Chem 74:123-128.
Lookhart GL. 1997. New methods helping to solve the gluten puzzle. Cereal Foods World 42:16-19.
Lookhart GL and Bean SR. 1997. Advances in cereal protein separation techniques. In: Proc Inter Symp on New Approaches to Functional Cereals Oils, Exhibition and Posters. Chinese Cereals and Oils Association (CCOA): Beijing, China. pp. 499-503.
Lookhart GL and Bean SR. 1997. Cereal proteins: composition of their major fractions and methods for identification. In: Handbook of Cereal Science and Technology (Kulp K and Ponte JG Jr eds), 2nd edition. Marcel Dekker, Inc: New York, NY. (In press).
Lookhart GL and Bietz JA. 1997. Wheat gluten's unique properties permit
many uses. In: PBI Bulletin. National Res Council of Canada. pp.
4-6.
Lookhart GL and Wrigley CW. 1997. Introduction of Session I. Biochemical
determinants for quality prediction. In: Proc Inter Wheat Quality
Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS.
pp. 41-43.
Martin CR, Sauer DB, Seitz LM, and Steele JL. 1997. Development of a grain odor sampler. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p. 504. (Abstr).
Martin CR and Steele JL. 1997. Physical properties measurement of single
corn kernels. Cereal Foods World Abstr 42:649.
Martin CR and Steele JL. 1997. The single kernel characterization system.
In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain
Industry Alliance: Manhattan, KS. p. 504. (Abstract)
McCluskey PJ, Chung OK, and Herrman TJ. 1997. Milling bread-baking qualities
of hard winter wheat varieties: 1997 Kansas update. MF-1077, Kansas State
Univ Agric Exp Stn and Cooperative Ext Serv. 4 pp.
Ohm JB and Chung OK. 1997. Hard winter wheat flour free lipids: relationships with wheat/flour quality factors and variations. Cereal Foods World Abstr 42:629.
Ohm JB, Chung OK, and Deyoe CW. 1997. Single kernel characteristics of hard winter wheats in relation to milling and baking quality. Cereal Chem (In press).
Park HS, Seib PA, Chung OK, and Seitz LM. 1997. Fortifying bread with three antioxidants. Cereal Chem 74:202-206.
Park HS, Seib PA, and Chung OK. 1997. Fortifying bread with a mixture of wheat fiber and psyllium husk fiber plus three antioxidants. Cereal Chem 74:207-211.
Park SH, Chung OK, and Seib PA. 1997. Starch properties in relation to bread crumb grain. Cereal Foods World Abstr 42:616-617.
Ram MS, Seitz LM, and Rengarajan, R. 1997. Use of an autosampler for dynamic-headspace extraction of volatile compounds from grains and effect of added water on extraction efficiency. Cereal Foods World Abstr 42:625.
Seabourn BW, Chung OK, and Seib PA. 1997. Near infrared reflectance spectroscopy of flour-water doughs during mixing. Cereal Foods World Abstr 42:612.
Sears RG, Martin TJ, Cox TS, Chung OK, Curran SP, Heer WF, and Witt MD. 1997. Registration of 'Arlin' wheat. Crop Sci 37:621.
Sears RG, Martin TJ, Cox TS, Chung OK, Curran SP, Heer WF, and Witt, M.D. 1997. Registration of 'Karl 92' wheat. Crop Sci 37:622.
Sears RG, Martin TJ, Hatchett JH, Cox TS, Bequette RK, Curran SP, Chung OK, Heer WF, Long JH, and Witt MD. 1997. Registration of '2137' wheat. Crop Sci 37:622.
Sears RG, Moffatt JM, Martin TJ, Cox TS, Bequette RK, Curran SP, Chung OK, Heer WF, Long JH, and Witt MD. 1997. Registration of 'Jagger' wheat. Crop Sci (In press).
Seitz LM, Rengarajan R, and Ram MS. 1997. Volatiles extracted from wheat
grain by supercritical carbon dioxide and direct helium purge. Cereal Foods
World Abstr 42:626.
Seitz LM, Rengarajan R, and Ram MS. 1997. Volatiles extracted from whole
and ground wheat grain by supercritical carbon dioxide and direct helium
purge. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK
eds). Grain Industry Alliance: Manhattan, KS. p. 502. (Abstract).
Shewry PR and Bechtel DB. 1997. Morphology and chemistry of the rye grain. In: Rye: Production, Chemistry, and Technology (Bushuk W ed). Am Assoc Cereal Chem, Inc: St. Paul, MN (In press).
Shogren MD, Steele JL, and Brabec DL. 1997. Mixograph instrumentation. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p. 505. (Abstract)
Spillman CK, Haque E, Reddy PV, Fang Q, and Steele JL. 1997. Development of an experimental roller mill. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p. 507. (Abstract)
Subramanyam Bh, Hagstrum DW, Meagher RL, Burkness E, Hutchinson WD, and Naranjo SE. 1997. Development and evaluation of sequential sampling plans for Cryptolestes ferrugineus (Stephens) (Coleoptera: Cucujidae) infesting farm-stored wheat. J Stored Prod Res 33:321-329.
Steele JL and Chung OK. 1997. Editors, Proc Inter Wheat Quality Conf. Grain Industry Alliance: Manhattan, KS. 542 pp.
Steele JL and Chung OK. Forword. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p. iii.
Wang D, Dowell FE, and Lacey RE. 1997. Effect of wheat kernel size and orientation on visible and near-infrared reflectance spectra and single wheat kernel color classification. ASAE Ann Meeting. Paper No. 97-3023.
Wang D, Dowell FE, and Lacey RE. 1997. The determination of single wheat kernel color class using visible and near-infrared reflectance. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p. 505. (Abstract)
Wrigley CW and Lookhart GL. 1997. Wheat protein as a quality determinant. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. pp. 51-59.
Zayas IY and Chung OK. 1997. Machine vision for pup loaves evaluation. Cereal Foods World Abstr 42:603.
Zayas IY and Chung OK. 1997. Digital imaging for bread assessment. In: Proc Inter Wheat Quality Conf (Steele JL and Chung OK eds). Grain Industry Alliance: Manhattan, KS. p. 506. (Abstract)
Zayas IY and Flinn PW. 1997. Detection of insects in bulk wheat samples with machine vision. ASAE Ann Inter Meeting. Paper No. 97-3149.