Wheat Storage Research Articles

Physio-chemical Qualities of Wheat Varieties as Influenced by Nitrogen and Sulfur Fertilization

Nitrogen and sulfur supplies have a strong influence on the physio-chemical characteristics of crop as well as on the quality and quantity of wheat storage proteins, which play an important role in bread-making process. In order to evaluate the contribution of soil and foliar fertilization of nitrogen and sulfur on quality assessment of wheat, a field trail was carried out having RCB design with four replications and eight different treatments of N and S combinations allotted to plots at different growth stages. Results indicated that highest gluten content (28.35%) was recorded when the wheat crop was fertilized with treatment number-6. Likewise minimum ash contents (1.83%) and minimum electrical conductivity was observed with fertilization of treatment number-8, while control practice result low gluten contents, low standard germination %age and minimum accelerated aging germination test value. In all the recorded observations concerning the experiment wheat cultivar Pirsabaq-2005 showed appreciable response as compared with other variety. So it is possible to obtain maximum quality assessment traits of wheat grain and flour through soil and foliar application of N and S.

Simulation of phosphine flow in vertical grain storage: a preliminary numerical study

To fumigate grain stored in a silo, phosphine gas is distributed by a combination of diffusion and fan-forced advection. This initial study of the problem mainly focuses on the advection, numerically modelled as fluid flow in a porous medium. We find satisfactory agreement between the flow predictions of two Computational Fluid Dynamics packages, Comsol and Fluent. The flow predictions demonstrate that the highest velocity ($>0.1$\,m/s) occurs less than $0.2$\,m from the inlet and reduces drastically over one metre of silo height, with the flow elsewhere less than $0.002$\,m/s or $1$\% of the velocity injection. The flow predictions are examined to identify silo regions where phosphine dosage levels are likely to be too low for effective grain fumigation. References K. Bullen, Insect control in stored grain, Technical report , DPIandF, Plant Science, Toowoomba, Queensland, 2007. http://www.dpi.qld.gov.au/26_6263.htm J. Canchun, D. W. Sun, and C. Cao, Computer simulation of temperature changes in a wheat storage bin, Journal of Stored Products Research , 37 , 165--177, 2001. doi:10.1016/S0022-474X(00)00017-5 P. J. Collins, G. J. Daglish, M. K. Nayak, P. R. Ebert, D. Schlipalius, W. Chen, H. Pavic, T. M. Lambkin, R. Kopittke, and B. W. Bridgeman, Combating resistance to phosphine in Australia, Proc. Int. Conf. Controlled Atmosphere and Fumigation in Stored Products , Executive Printing Services, 593--607, 2001. http://www.ftic.info/CAFSITE/CAFPDF/60.pdf Comsol (2008). Comsol multiphysics user's guide. http://www.comsol.com P. W. Flinn and C. Reed, Effects of outside air temperature on movement of phosphine gas in concrete elevator bins, Proceedings of the International Conference on Controlled Atmosphere and Fumigation in Stored Products , 704--706, 2008. Fluent, Ansys inc. http://www.ansys.com A. K. Singh and G. R. Thorpe, A solution procedure for three-dimensional free convective flow in peaked bulks of grain, Journal of Stored Products Research , 29 , 221--235, 1993. doi:10.1016/0022-474X(93)90004-N E. A. Smith, D. S. Jayas, and A. D. Ville, Modelling the flow of carbon dioxide through beds of cereal grains, Transport in Porous Media , 44 , 123--144, 2001. doi:10.1023/A:1010760508392 E. A. Smith and D. S. Jayas, Modeling the movement of fumigant gas within grain beds, American Society of Agricultural Engineers , 44(3) , 661--667, 2001. http://asae.frymulti.com S. Xu, D. S. Jayas, N. D. G. White, and W. E. Muir, Momentum-diffusive model for gas transfer in granular media, Journal of Stored Products Research , 38 , 455--462, 2002. doi:10.1016/S0022-474X(01)00048-0

In vitro degradation of wheat gluten fractions by Fusarium graminearum proteases

Fusarium spp. infection of cereal grain is a common problem, which leads to a dramatic loss of grain quality. The aim of the present study was to investigate the effect of Fusarium infection on the wheat storage protein gluten and its fractions, the gliadins and glutenins, in an in vitro model system. Gluten proteins were digested by F. graminearum proteases for 2, 4, 8 and 24 h, separated by Osborne fractionation and characterised by chromatographic (RP-HPLC) and electrophoretic analysis (SDS-Page). Gluten digestion by F. graminearum proteases showed in comparison with gliadins a preference for the glutenins whereas the HMW subfraction was at most affected. In comparison with a untreated control, the HMW subfraction was degraded of about 97% after 4 h incubation with Fusarium proteases. Separate digestion of gliadin and glutenin underlined the preference for HMW-GS. Analogue to the observed change in the gluten composition, the yield of the proteins extracted changed. A higher amount of glutenin fragments was found in the gliadin extraction solution after digestion and could mask a gliadin destruction at the same time. This observation can contribute to explain the frequently reported reduced glutenin amount parallel to an increase in gliadin quantity after Fusarium infection in grains.

Comparative Study of the Effect of Incorporated Individual Wheat Storage Proteins on Mixing Properties of Rice and Wheat Doughs

The aim of this work was to compare the effects of incorporated wheat storage proteins on the functional properties of rice and wheat flours. The advantage of rice as a base flour compared to wheat is that it does not contain any wheat flour components and, therefore, has no interactive effect between wheat glutenin proteins. The incorporation of individual HMW glutenin subunit proteins (Bx6, Bx7, and By8) in different ratios had significant positive effects on the mixing requirements of both rice and wheat doughs. Reconstitution experiments using two x+y type HMW-GS pairs together with a bacterially expressed LMW-GS have been also carried out in this study. The largest effects of polymer formation and mixing properties of rice flour dough were observed when Bx and By subunits were used in a 1:1 ratio and HMW and LMW glutenin subunits in a 1:3 ratio. However, using the same subunit ratios in wheat as the base flour, these synergistic effects were not observed.

Toxicity of some plant powders to maize weevil, Sitophilus zeamais (motschulsky) [Coleoptera: Curculiondae] on stored wheat grains (Triticum aestivum)

This research reported the effect of four plant powders including Azadirachta india, Alstonia boonei, Garcina kola and Moringa oleifera on the mortality adults and emergence of maize weevil (Sitophilus zeamais) on stored wheat grains. The powders were incorporated into 20 g of wheat grains at 0.0% (control) 2.5, 5.0, 12.5 and 25.5% (w/w). The ability of the plants powders to protect wheat grains were assessed in terms of mortality rates after 24 to 96 h of post treatment, percentage grain weight loss and damage after the first filial generation (F1). The results indicated that A. indica and A. boonei provide the highest protection of the treated grains. G. kola and M. oleifera were not good enough protectants at the concentrations tested. These plants powders did not adversely affect seed viability after three months of storage, suggesting that seeds treated with A. indica, A. boonei, G. kola and M. oleifera are suitable for consumption and planting stock. Seed powders of A. boonei can be used as a good alternative to pesticides against S. zeamais in addition with that of A. indica which effects are well established by many former works. Key words: Sitophilus zeamais, Azadirachta indica, Alstonia boonei, Garcina kola, Moringa oleifera,wheat storage.

Expression of a new chimeric protein with a highly repeated sequence in tobacco cells

In wheat, the high-molecular weight (HMW) glutenin subunits are known to contribute to gluten viscoelasticity, and show some similarities to elastomeric animal proteins as elastin. When combining the sequence of a glutenin with that of elastin is a way to create new chimeric functional proteins, which could be expressed in plants. The sequence of a glutenin subunit was modified by the insertion of several hydrophobic and elastic motifs derived from elastin (elastin-like peptide, ELP) into the hydrophilic repetitive domain of the glutenin subunit to create a triblock protein, the objective being to improve the mechanical (elastomeric) properties of this wheat storage protein. In this study, we investigated an expression model system to analyze the expression and trafficking of the wild-type HMW glutenin subunit (GS(W)) and an HMW glutenin subunit mutated by the insertion of elastin motifs (GS(M)-ELP). For this purpose, a series of constructs was made to express wild-type subunits and subunits mutated by insertion of elastin motifs in fusion with green fluorescent protein (GFP) in tobacco BY-2 cells. Our results showed for the first time the expression of HMW glutenin fused with GFP in tobacco protoplasts. We also expressed and localized the chimeric protein composed of plant glutenin and animal elastin-like peptides (ELP) in BY-2 protoplasts, and demonstrated its presence in protein body-like structures in the endoplasmic reticulum. This work, therefore, provides a basis for heterologous production of the glutenin-ELP triblock protein to characterize its mechanical properties.

Kinetics of Heat-Induced Polymerization of Gliadin

The kinetics of heat-induced polymerization of gliadin, that is, a mixture of monomeric wheat storage proteins, was studied using a model system. Samples were heated at pH 6.0 and 8.0 at 110, 120, and 130 °C for up to 240 min, and their extractabilities were compared under nonreducing and reducing (with 1% dithiothreitol) conditions. Extraction media were sodium dodecyl sulfate (SDS) containing buffer (pH 6.8, SDS buffer) and/or 70% ethanol. Gliadin cross-linking mainly resulted from intermolecular disulfide (SS) bond formation. At higher temperatures and, preferably, alkaline pH, intramolecular SS bonds in gliadin underwent β-elimination reactions, leading to the formation of dehydroalanine (DHA) and free sulfhydryl (SH) groups. The latter interchanged rapidly with SS bonds, leading to intermolecular SS bonds and gliadin extractability loss. When free SH groups had been formed, gliadin extractability in SDS buffer decreased following first-order reaction kinetics, the reaction rate constant of which increased with temperature and pH. Furthermore, the extractabilities of α- and γ-gliadin in 70% ethanol decreased according to first-order reaction kinetics. ω-Gliadin extractability was much less affected. Under the experimental conditions, gliadin polymerization through SH-SS interchange occurred much more rapidly than β-elimination of cystine.

Studies on effect of additives on protein profile, microstructure and quality characteristics of pasta

Wheat storage proteins play a vital role in pasta making quality. In the present study, SDS-PAGE, Gel filtration chromatography and Scanning electron microscopy techniques were employed to understand the changes in the wheat protein fractions and their interactions with additives namely Sodium Steroyl Lactate (SSL), Glycerol Monostearate (GMS) and Hydroxy Propyl Methyl Cellulose (HPMC) during processing of pasta. SDS-PAGE studies indicated changes in High Molecular Weight Glutenin (HMW) fractions during drying stages of pasta preparation and in cooked pasta samples. In uncooked pasta, gel filtration patterns showed four peaks corresponding to different storage proteins whereas in the case of cooked pasta, these peaks were merged into three peaks. Pasta quality characteristics studies indicated that pasta with HPMC was found to have minimum percentage of cooking loss (5.6%), increased cooked weight (82g), firmness (2.97N) and high overall quality score (27) than GMS, SSL and control. Microstructure studies confirm the beneficial effect of HPMC. The present study indicated that HPMC is better additive for pasta manufacture followed by GMS. This could be due to interaction of HPMC with starch and protein matrix is different from that of GMS and SSL.

Kernel Elastic Properties and Sedimentation: Influence of High and Low Molecular Weight Glutenin Allelic Composition

Cereal ChemistryVolume 88, Issue 1 p. 41-44 Note Kernel Elastic Properties and Sedimentation: Influence of High and Low Molecular Weight Glutenin Allelic Composition J. D. C. Figueroa, J. D. C. Figueroa Centro de Investigación y de Estudios Avanzados. (CINVESTAV-Unidad Querétaro), Libramiento Norponiente 2000, Fracc. Real de Juriquilla, Querétaro, C.P. 76230 Qro., México. Corresponding author. E-mail: [email protected] Robert M. Kerr Food & Agricultural Products Center, Oklahoma State University, 123 FAPC, Stillwater, OK 74078-6055.Search for more papers by this authorR. J. Peña, R. J. Peña CIMMYT, km 45 Carretera México Veracruz El Batán, Texcoco, México C.P. 56130.Search for more papers by this authorT. Maucher, T. Maucher Centro de Investigación y de Estudios Avanzados. (CINVESTAV-Unidad Querétaro), Libramiento Norponiente 2000, Fracc. Real de Juriquilla, Querétaro, C.P. 76230 Qro., México. University of Applied Science Furtwangen, Jacob-Kienzle Str. 17, 78054 Villingen-Schwenningen, Germany.Search for more papers by this authorP. Rayas-Duarte, P. Rayas-Duarte Robert M. Kerr Food & Agricultural Products Center, Oklahoma State University, 123 FAPC, Stillwater, OK 74078-6055.Search for more papers by this authorK. Khan, K. Khan Department of Cereal and Food Sciences, North Dakota State University, 111 Harris Hall, Dept 7640, P.O. Box 6050, Fargo, ND 58108-6050.Search for more papers by this author J. D. C. Figueroa, J. D. C. Figueroa Centro de Investigación y de Estudios Avanzados. (CINVESTAV-Unidad Querétaro), Libramiento Norponiente 2000, Fracc. Real de Juriquilla, Querétaro, C.P. 76230 Qro., México. Corresponding author. E-mail: [email protected] Robert M. Kerr Food & Agricultural Products Center, Oklahoma State University, 123 FAPC, Stillwater, OK 74078-6055.Search for more papers by this authorR. J. Peña, R. J. Peña CIMMYT, km 45 Carretera México Veracruz El Batán, Texcoco, México C.P. 56130.Search for more papers by this authorT. Maucher, T. Maucher Centro de Investigación y de Estudios Avanzados. (CINVESTAV-Unidad Querétaro), Libramiento Norponiente 2000, Fracc. Real de Juriquilla, Querétaro, C.P. 76230 Qro., México. University of Applied Science Furtwangen, Jacob-Kienzle Str. 17, 78054 Villingen-Schwenningen, Germany.Search for more papers by this authorP. Rayas-Duarte, P. Rayas-Duarte Robert M. Kerr Food & Agricultural Products Center, Oklahoma State University, 123 FAPC, Stillwater, OK 74078-6055.Search for more papers by this authorK. Khan, K. Khan Department of Cereal and Food Sciences, North Dakota State University, 111 Harris Hall, Dept 7640, P.O. Box 6050, Fargo, ND 58108-6050.Search for more papers by this author First published: 15 February 2011 https://doi.org/10.1094/CCHEM-10-09-0142Citations: 5AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume88, Issue1January/February 2011Pages 41-44 RelatedInformation

Antibodies to the Wheat Storage Globulin Glo-3A in Children Before and at Diagnosis of Celiac Disease

Antibodies to the Wheat Storage Globulin Glo-3A in Children Before and at Diagnosis of Celiac Disease

Aeration Strategy Simulations for Wheat Storage in the Sub-Tropical Region of North India

Ambient aeration is typically used in temperate climates to preserve grains by cooling, preventing moisture migration, and maintaining temperature as low and uniform throughout the grain mass as possible. However, the climatic factors for wheat bulk storage in the sub-tropical climate of north India are challenging for the grain preservation process. Low relative humidity with high temperature during daytime and high relative humidity with low temperature during nighttime is the common phenomenon. Five years of weather data were analyzed using the modified Chung-Pfost EMC equation for wheat. Fifteen different aeration strategies were formulated based on the weather data during the maintenance period (June to September) and cooling period (October to March). Strategies were selected based on combinations of the following parameters: temperature control; EMC control; 1 h, 2 h, or 4 h morning and/or evening aeration; and 0.11, 0.34, and 0.67 m3 min-1 t-1 airflow rate. These 15 aeration strategies for the sub-tropical weather conditions of north India were studied using the 2D PHAST-FEM model developed at Purdue University. The initial grain temperature and moisture were assumed as 27°C and 12% (w.b.), respectively, based on typical harvest conditions. Dry matter loss (DML), insect development, fan run hours, and average grain temperature and moisture content for these aeration strategies were quantified based on weather data from 2000-2001 to 2004-2005. Aeration strategies were selected based on the optimum combination of low values of DML, insect development, grain temperature, moisture content, and fan run hours during both the maintenance and cooling periods . The best strategy was to operate fans 4 h during the morning and evening with an airflow of 0.11 m3 min-1 t-1, with EMC control but without temperature control during the maintenance period and with both EMC and temperature control during the cooling period (strategy 13).

Antibodies from a Patient with Type 1 Diabetes and Celiac Disease Bind to Macrophages that Express the Scavenger Receptor CD163

Antibodies against the wheat storage globulin Glo-3A from a patient with both type 1 diabetes (T1D) and celiac disease were enriched to identify potential molecular mimicry between wheat antigens and T1D target tissues. Recombinant Glo-3A was used to enrich anti-Glo-3A immunoglobulin G antibodies from plasma by batch affinity chromatography. Rat jejunum and pancreas, as well as human duodenum and monocytes were probed, and binding was evaluated by immunohistochemistry and confocal microscopy. Glo-3A-enriched antibodies bound to a specific subset of cells in the lamina propria of rat jejunum that co-localized mostly with a marker of resident, alternatively activated CD163-positive (CD163⁺) macrophages. Blood monocytes and macrophage-like cells in human duodenum were also labelled with the enriched antibodies. Blocking studies revealed that binding to CD163⁺ macrophages was not due to cross-reactivity with anti-Glo-3A antibodies, but rather to non-Glo-3A antibodies co-purified during antibody enrichment. The novel finding of putative autoantibodies against tolerogenic intestinal CD163⁺ macrophages suggests that regulatory macrophages were targeted in this patient with celiac disease and T1D.

Antibodies to the Wheat Storage Globulin Glo‐3A in Children Before and at Diagnosis of Celiac Disease

Celiac disease (CD) is an autoimmune disease triggered by exposure to gluten-containing foods. IgA autoantibodies to tissue transglutaminase (TTG) are elevated in CD, but little is known about the gastrointestinal state before the appearance of TTG. Antibodies to wheat storage globulin Glo-3A have been studied in type 1 diabetes, and may be a marker of altered mucosal barrier and/or immune function. In the present study, we investigated antibody responses to Glo-3A in CD. In the Diabetes Autoimmunity Study in the Young, children were studied prospectively from birth for the appearance of TTG and CD. Fifty cases of CD were frequency matched with 50 controls on age (of TTG seroconversion in the case), sex, ethnicity, presence of a first-degree relative with type 1 diabetes mellitus, and human leukocyte antigen -DR3 genotype. In cases and controls, IgG antibodies to Glo-3A were analyzed in a blinded manner in the sample collected at the time of seroconversion to TTG positivity (or the matched sample in controls) and in all of the previous samples since birth (mean 4.5 samples). The association between Glo-3A antibody levels and CD case status was explored using t tests at the TTG-positive visit and when Glo-3A levels were highest, and mixed modeling to describe Glo-3A over time. At the time of first elevated TTG (mean 4.9 years), patients with CD had higher Glo-3A antibody levels than controls (13.3 ± 17.2 vs 7.6 ± 11.7, P = 0.005). In both cases and controls, Glo-3A antibodies appear to peak at a mean age of 2.9 years, before mean age of initial TTG seroconversion. The peak Glo-3A antibody levels were higher in cases than controls (25.5 ± 21.8 vs 14.9 ± 18.3 P = 0.0007). Using mixed modeling to account for multiple visits per person, cases had higher levels of Glo-3A antibodies than controls at all ages from birth to TTG seroconversion (β = 0.53, P = 0.002). Compared with controls, CD cases have higher Glo-3A antibody responses in the beginning years, before initial detection of TTG.

A Universal Approach to Eliminate Antigenic Properties of Alpha-Gliadin Peptides in Celiac Disease

Celiac disease is caused by an uncontrolled immune response to gluten, a heterogeneous mixture of wheat storage proteins, including the α-gliadins. It has been shown that α-gliadins harbor several major epitopes involved in the disease pathogenesis. A major step towards elimination of gluten toxicity for celiac disease patients would thus be the elimination of such epitopes from α-gliadins. We have analyzed over 3,000 expressed α-gliadin sequences from 11 bread wheat cultivars to determine whether they encode for peptides potentially involved in celiac disease. All identified epitope variants were synthesized as peptides and tested for binding to the disease-associated HLA-DQ2 and HLA-DQ8 molecules and for recognition by patient-derived α-gliadin specific T cell clones. Several specific naturally occurring amino acid substitutions were identified for each of the α-gliadin derived peptides involved in celiac disease that eliminate the antigenic properties of the epitope variants. Finally, we provide proof of principle at the peptide level that through the systematic introduction of such naturally occurring variations α-gliadins genes can be generated that no longer encode antigenic peptides. This forms a crucial step in the development of strategies to modify gluten genes in wheat so that it becomes safe for celiac disease patients. It also provides the information to design and introduce safe gluten genes in other cereals, which would exhibit improved quality while remaining safe for consumption by celiac disease patients.

Towards allelic diversity in the storage proteins of old and currently growing tetraploid and hexaploid wheats in Portugal

Using sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE), the different alleles encoded at the 6 glutenin loci and 3 ω-gliadin loci were identified from a set of 134 hexaploid and 128 tetraploid wheat accessions mainly grown in Portugal. In the hexaploid wheats (T. aestivum L.), a total of 56, 42 and 36 patterns were observed for high molecular weight-glutenin subunits (HMW-GS), low molecular weight-glutenin subunits (LMW-GS) and ω-gliadins respectively. For HMW-GS encoded at Glu-A1, Glu-B1 and Glu-D1 loci, 4, 10 and 6 alleles were observed, respectively. LMW-GS displayed similar polymorphism, as Glu-A3,Glu-B3 and Glu-D3 loci, which comprises 5, 9 and 3 alleles. Twenty-four alleles were observed for ω-gliadins found at Gli-A1, Gli-B1 and Gli-D1 loci with, 5, 16 and 3 alleles respectively. For tetraploid collection fifty different alleles were identified for the seven loci studied Glu-A1 (3), Glu-B1 (13), Glu-A3 (6), Glu-B3 (7), Glu-B2 (2), Gli-A1 (5) and Gli-B1 (14). The genetic distances within hexaploid and tetraploid wheats were presented using cluster representation. The mean value of genetic variation indices (H) for wheat storage protein loci was slightly lower in current commercially available varieties (0.592) and highest for old varieties (0.574).

Quality and Sensory Characteristics of Hard Red Wheat after Residential Storage for up to 32 Y

Samples of hard red wheat packaged for long-term storage, ranging in age from 0 to 32 y, were obtained from donors in residential households. All samples had been stored under nonabusive conditions (7% to 10% moisture, 13 to 27 °C). Selected quality parameters of the wheat (moisture, thiamin, free fatty acids, flour extraction rate, bread loaf volume, and bread firmness) and sensory properties of bread made from the stored wheat (aroma, appearance, texture, flavor, overall liking, acceptance for use as part of the regular diet, and acceptance for use in emergency situations) were evaluated. Free fatty acids increased significantly from 0.897 to 11.8 μmol/g, and flour extraction rate decreased significantly from 76.5% to 69.9% over time. None of the other quality parameters measured (moisture, thiamin, bread loaf volume, and bread firmness) were significantly correlated with wheat storage time. Panelists who frequently or occasionally consume whole wheat bread rated all breads made from the stored wheat with hedonic scores (9-point scale) of at least 6.4 (like slightly to moderately). Consumer ratings of bread texture, flavor, and overall acceptability were negatively correlated with storage time (P < 0.001); however, at least 70% of panelists indicated that they would consume the bread as part of their regular diet even after 32 y of wheat storage, while over 97% would do so in an emergency. These data indicate that wheat maintains nutritional quality and makes acceptable bread when stored up to 32 y at 13 to 27 °C and 7% to 10% moisture. Practical Application: Wheat stored for the purposes of disaster relief has the potential of being stored for extremely long periods of time, which may result in undesirable changes in milling and baking quality. Therefore, we tested wheat that had been stored under residential conditions for up to 32 y to determine its functional quality and consumer acceptability. Our results indicate that wheat of low moisture (7% to 10%) packaged in sealed cans and stored for up to 32 y at or below typical room temperature retains quality and can be made into bread that is well accepted by consumers. Thus, whole wheat has good long-term storage stability and can be recommended for emergency food supplies.

Root Growth and Soil Water Dynamics in Relation to Inorganic and Organic Fertilization in Maize–Wheat

Agricultural productivity is increasingly becoming dependent upon soil fertility, which is generally thought to be supplemented through the application of nutrients mainly through inorganic fertilizers. The present study aims to characterize the soil physical environment in relation to long-term application of farmyard manure (FYM) and inorganic fertilizers in a maize–wheat cropping system. The treatments in both the maize and wheat systems included a control (without any fertilizer or FYM), FYM (farmyard manure at 20 t ha−1), N100 (nitrogen at 100 kg ha−1), N100P50 (nitrogen and phosphorus at 100 and 50 kg ha−1), and N100P50K50 (nitrogen, phosphorus, and potash at 100, 50, and 50 kg ha−1). The treatments were replicated four times in a randomized complete block design in sandy loam soil. The root mass density in surface layers of both the crops was lower in FYM and higher in inorganic fertilizer plots. The root length density was found to be highest in FYM-treated plots and lowest in control plots. The periodic soil matric suction during wheat following maize remained highest in FYM plots followed by that in N100 plots in all the layers. The soil water storage of wheat at harvest (rice–wheat) was highest (21.1 cm) in control and lowest (17.8 cm) in FYM-treated plots. The soil water status, root growth, and crop performance improved with balanced fertilization.

Storage of wheat at high moisture

Deterioration rates were determined for 15-19% moisture content wheat (Dropia cultivar) stored at constant temperatures.Deterioration rates were determined by measuring germination capacity of the grain and respiration rates of grain. Safe storagetime was defined as the time for germination to decrease to 90%. Safe storage times of 19% m.c. wheat stored at constanttemperatures ranged from 2.5 d at 30 and 35°C to 37 d at 10°C. Deterioration rates of 19% m.c. wheat stored with a step decreasein storage temperatures (35-25, 30-20, 25-20, and 20-15°C) were determined and safe storage times were satisfactorily predicted.Safe storage times of 17% m.c. wheat were 5, 7, and 15 d at 35, 30, and 25°C, respectively. Respiration rates and germinationpercentages of 15 and 16% m.c. wheat stored at 25°C remained constant for 70 d. The respiration rates of 17-19% m.c. wheat at25°C increased while the germination percentages decreased with storage time. Germination dropped from 98 to 92-89% when thedry matter losses were about 0.05% and visible mould occurred when the dry matter losses were about 0.1% in 17-19% m.c.wheat.

Simulation model of the red flour beetle in flour mills.

Simulation model of the red flour beetle in flour mills.

The Kinetics of β-Elimination of Cystine and the Formation of Lanthionine in Gliadin

When gliadin, a mixture of wheat storage proteins containing only intramolecular disulfide (SS) bonds, is heated at high temperatures and preferably at alkaline pH, the SS bonds are cleaved by β-elimination reactions leading to decreased cystine levels and the generation of dehydroalanine (DHA) and free sulfhydryl (SH) groups. DHA and the free SH group of cysteine can further react to form the irreversible cross-link lanthionine (LAN). The kinetics of this reaction were studied by heating model systems containing gliadin at different pH values (pH 6.0, 8.0 and 11.0) at temperatures up to 120 °C. Multiresponse modeling was applied to simultaneously describe the course of the reaction partners, intermediates and products. The estimated kinetic parameters indicate that the reaction rate constant for the elimination reaction increases with temperature and pH. Moreover, the predominant reaction consuming the intermediary DHA is the cross-link with cysteine to form LAN following second-order reaction kinetics. The corresponding reaction rate constant is less dependent on temperature and pH. Use of the proposed kinetic model to estimate reaction product concentrations in cereal-based foods allowed us to conclude that the β-elimination reaction may be less important during, e.g., bread making, but may well contribute to gluten network formation during the production of soft wheat products. It may also well be relevant in the production of bioplastics made from gluten.