Wheat Grain (wheat + grain)

Distribution by Scientific Domains


Selected Abstracts


Effects of Post-Anthesis Drought and Waterlogging on Accumulation of High-Molecular-Weight Glutenin Subunits and Glutenin Macropolymers Content in Wheat Grain

JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 2 2009
D. Jiang
Abstract Drought and flooding during grain filling have become major constraints to wheat quality and yield. The impacts of water deficits and waterlogging during the grain filling on contents of high-molecular-weight glutenin subunits (HMW-GS) and of glutenin macropolymers (GMP) in grains of the winter wheat cultivar Yumai 34 with high grain protein content (GPC) and Yangmai 9 with low GPC were studied. At maturity, GPC was higher under drought and lower under waterlogging compared to the control, while contents of GMP and HMW-GS were reduced by the two water-stress treatments. The contents of both HMW-GS and GMP were higher in Yumai 34 than in Yangmai 9. A drought event after anthesis increased the accumulation of HMW-GS during the early grain filling stage. By contrast, waterlogging reduced the accumulation of HMW-GS during the whole grain filling phase. At maturity, the HMW-GS and GMP to protein ratios were also depressed under the two water-stress events, while the HMW-GS to GMP ratio was very close between the three treatments in Yumai 34 and much higher under the control than the drought and waterlogging treaments in Yangmai 9. It is concluded that the variation in GMP content with various water-stress treatments is attributed to the changing in accumulation of HMW-GS in the grain. [source]


Sensory Profiles of Bread Made from Paired Samples of Organic and Conventionally Grown Wheat Grain

JOURNAL OF FOOD SCIENCE, Issue 4 2007
L.E. Annett
ABSTRACT:, The Canadian hard red spring wheat cultivar "Park" was grown in 2005 in Edmonton, AB, Canada on both conventionally and organically managed land, situated less than 1 km apart. Grains from the paired wheat samples were compared for cereal-grain-quality attributes. For sensory analysis, organically and conventionally produced wheat grains were milled into flour and baked into 60% whole wheat bread. Color, texture, taste, and aroma attributes of bread were compared using the sensory technique of descriptive analysis. Organic grain contained more wholemeal protein than conventional grain (P, 0.05), but both were greater than 14% protein, indicating excellent grain quality for yeast-leavened bread. Mixograph analysis revealed that conventional flour produced stronger bread dough than organic flour (P, 0.05). Visual observation confirmed these findings as conventional flour produced larger bread loaf volume. Fourteen sensory attributes were generated by the descriptive analysis panel. No differences were observed for flavor, aroma, or color attributes (P > 0.05), but the panel perceived the organic bread to be more "dense" in texture (P, 0.05) with smaller air cells in the appearance of the crumb (P, 0.05) than conventional bread. [source]


A mini-bag technique for evaluation of fungicide effects on Trichoderma spp in mushroom compost

PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 4 2004
Salem O Abosriwil
Abstract An in vivo technique was developed to observe colonisation of mushroom compost by Trichoderma spp. Isolates of T harzianum (Th2), T harzianum (Th1), T koningii (Tk) and T viride (Tv) were artificially introduced into compost using a mini-bag system. Wheat grains, colonised by Trichoderma spp, were placed centrally on a layer of compost at the bottom of 1-litre polythene bags which were then filled with 350 g of spawned or un-spawned compost, and partially sealed. After 14 and 21 days incubation at 27 °C, the bags were assessed for recovery of Trichoderma from middle and top zones using a needle stab re-isolation technique and a visual colonisation scoring system. Visible green mould contamination, similar to that observed in practice, developed within 21 days. The visual colonisation scoring was reliably related to the re-isolation success. In this evaluation, Trichoderma spp showed considerable differences in their relative abilities to colonise spawned and un-spawned compost, with Th2 isolates being consistently superior to the other isolates of Th1, Tk and Tv in colonising spawned compost. This technique was employed to evaluate the effects of fungicides on the colonisation of mushroom compost by three Trichoderma spp: Th2, Th1 and Tk, using 1-litre and 5-litre mini-bag systems. Aqueous suspensions of benomyl, carbendazim, thiabendazole, prochloraz and prochloraz + carbendazim incorporated into the compost at 50 mg litre,1, or applied to spawn at 50 mg kg,1, reduced the colonisation by Trichoderma spp. Prochloraz and prochloraz + carbendazim were superior to benomyl, carbendazim or thiabendazole in reducing compost colonisation by Th2, Th1 and Tk, with Th2 being the most persistent type, capable of colonising treated compost in the presence of all five fungicides. The prochloraz + carbendazim mixture, not normally used in mushroom production, was equal to or better than prochloraz alone. The incidence of green mould colonisation by Th2 was as extensive in the 5-litre compost bags as in the 1-litre bags, but colonisation by Th1 and Tk was more apparent in the 5-litre bags. The in vivo mini-bag evaluations using wheat grain Trichoderma inoculum and needle stab re-isolation procedures proved an efficient method for studying colonisation and screening for effectiveness of fungicides applied to mushroom compost or spawn. Copyright © 2003 Society of Chemical Industry [source]


Effect of gamma-ray irradiation on the physicochemical properties of flour and starch granule structure for wheat

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2009
Jun Wang
Summary Effect of gamma irradiation on the physicochemical properties of flour and starch granule structure of wheat was compared to non-irradiated wheat. The moisture content of wet gluten and titratable acidity of wheat flour were significantly affected by gamma irradiation. This treatment also destroyed the starch granules of wheat grain and their breakage augmented as the dose of gamma irradiation increased, apparently resulting in the increase of small starch granules. Probably, these results were due to the disruption of large molecule, such as proteins, lipids and starch. The irradiated wheat flour for RVA pasting properties (flour viscosity) was also evaluated. Besides the difference in RVA profile, starch pasting curves showed a considerable decrease for six main parameters as gamma irradiation dose at different velocity increased. [source]


The effect of wheat ,-amylase inhibitors incorporated into wheat-based artificial diets on development of Sitophilus granarius L., Tribolium confusum Duv., and Ephestia kuehniella Zell

JOURNAL OF APPLIED ENTOMOLOGY, Issue 4 2002
J. R. Warchalewski
Artificial grain kernels made from ground wheat grain, commercial wheat starch and wheat proteinaceous ,-amylase inhibitors were used as diets for adults of the granary weevil (Sitophilus granarius L). For the confused flour beetle (Tribolium confusum Duv.) and the Mediterranean flour moth (Ephesitia kuehniella Zell.), a friable mixture of the diets was used. The results of feeding trials showed that the survival of S. granarius adults was not correlated with the soluble proteins extracted from wheat and amylolytic activity located in this protein fraction. On the other hand, the weight of dust (the index of feeding intensity) produced during feeding depended on the presence of ,-amylase and trypsin inhibitors in wheat-based diets. Ephesitia kuehniella larvae did not develop at all on a diet consisting of 50% wheat starch and 50% crude ,-amylase inhibitors from wheat. The same diet lengthened the development time of T. confusum larvae by 15.1 days. These results attest to the existence of a specific native enzymatic apparatus in the alimentary canals of these three grain pests. However, the highly active insect ,-amylase inhibitors appear to have a limited influence on the developmental parameters studied although some reduction of insects populations might be expected. [source]


Occurrence and Distribution of Microdochium and Fusarium Species Isolated from Durum Wheat in Northern Tunisia and Detection of Mycotoxins in Naturally Infested Grain

JOURNAL OF PHYTOPATHOLOGY, Issue 9 2009
Lobna Gargouri Kammoun
Abstract An outbreak of Fusarium Head Blight of durum wheat occurred in 2004 being localized in sub-humid and higher semi-arid region of Northern Tunisia. A mycological survey carried out throughout these regions, revealed that 78% of the prospected fields were infested. Results of the morphological and molecular identification, showed that the most common species isolated from diseased wheat spikes was Microdochium nivale var. nivale (63.5%), followed by Fusarium culmorum (26%), F. pseudograminearum (9%) and F. avenaceum (1.5%). To evaluate mycotoxin content of naturally infected grain, the amounts of trichothecene mycotoxin deoxynivalenol (DON) in harvested grain from 45 fields were quantified by RIDASCREEN DON Enzyme Immunoassay Kit (ELISA). This study showed that the infection levels in freshly harvested grain were very low and the maximum deoxynivalenol (DON) level of the positive samples was 53 ppb. This is the first report on the natural occurrence of DON in naturally infected wheat grain sampled from Northern Tunisia. [source]


Cadmium concentration in durum wheat grain (Triticum turgidum) as influenced by nitrogen rate, seeding date and soil type

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2010
Patrizia Perilli
Abstract BACKGROUND: Cadmium (Cd) is a trace element that has been associated with various human health problems. Cd enters plants, either by direct absorption through leaves or by uptake from soils, allowing Cd into the food chain. Nitrogen (N) fertilizer management is important in optimizing crop yield and protein content of durum wheat, but may influence Cd availability and hence Cd concentration in crops, with the effects being strongly influenced by environmental conditions and crop cultivar. RESULTS: In field studies, Cd and protein concentration in durum wheat grain differed between cultivars and were strongly affected by N application, with only minor effects of N occurring on concentration and uptake of P and Zn. Protein content increased significantly with N application in five of six site-years, with the response being generally independent of cultivar and seeding data. Cd concentration also increased with N application in five of six seeding dates, with the response being greater in AC Melita than Arcola in three of the six site-years. There were large differences in Cd concentration from year to year and with seeding date, indicating a strong environmental influence. CONCLUSIONS: This study shows that different cultivars accumulate different levels of Cd in the grain and that seeding date and nitrogen fertilizer management can influence grain Cd concentration, with the magnitude of effects varying with environmental factors. In the future we may be able to manipulate management practices to optimize protein concentration and minimize Cd concentration in durum wheat, which could help to address the health and safety concerns of consumers. © Society of Chemical Industry and Her Majesty the Queen in right of Canada [source]


In situ evaluation of the protein value of wheat grain corrected for ruminal microbial contamination

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2009
José M Arroyo
Abstract BACKGROUND: Uncorrected and microbial corrected in situ estimates of ruminal effective degradability (RED) of dry matter (DM), organic matter (OM) and crude protein (CP) and intestinal effective digestibility (IED) of DM and CP of a wheat grain sample were obtained by a simplified method using a sample pooled from rumen-incubated residues representing rumen outflow of undegraded food. Uncorrected values of RED of DM and CP were also obtained by the usual mathematical integration method. The study was performed in three rumen and duodenum cannulated wethers. RESULTS: Uncorrected values of RED of CP were similar either for the mathematical integration or this simplified method (82.4% vs. 82.2%). Microbial contamination in the rumen led to small underestimations (P < 0.05) of RED of DM (87.9% vs. 88.1%) and CP (82.2% vs. 82.8%) and to small overestimations (P < 0.05) of IED for DM (66.5% vs. 66.1%) and CP (87.7% vs. 87.3%). Accumulative errors resulted in overestimations (P < 0.05) of the intestinal digested fractions of DM (1.8%) and CP (4.0%). CONCLUSION: Corrected values of intestinal digested CP show that the protein value of wheat is closely related to the microbial protein synthesis derived from its OM rumen fermentation. This synthesis and the content of intestinal digested undegraded protein may be respectively higher and lower than is usually assumed in feed tables. Copyright © 2009 Society of Chemical Industry [source]


Zinc bioavailability in wheat grain in relation to phosphorus fertiliser, crop sequence and mycorrhizal fungi

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2008
Megan H Ryan
Abstract BACKGROUND: While human diets are often deficient in zinc (Zn), the impacts of crop management on Zn in cereal grains are rarely examined. In this study the effect of phosphorus (P) fertiliser and crop sequence (wheat following canola, linola, fallow or pasture) on wheat grain Zn concentration and bioavailability for humans was investigated. RESULTS: The Zn concentration of wheat grain decreased by 33,39% in response to P fertiliser. It was also 30,40% lower for crops following canola and fallow than for those following linola and pasture. P fertiliser decreased the colonisation of arbuscular mycorrhizal fungi (AMF) in wheat roots, and canola and fallow led to lower colonisation than linola and pasture. Since AMF are known to assist in soil uptake of immobile nutrients such as Zn, it is hypothesised that P fertiliser and crop sequence affected grain Zn concentration through AMF. P fertiliser also increased the concentrations of grain P by 17% and grain phytic acid (PA) by 19%, but had little effect on the concentrations of calcium (Ca), iron (Fe) and polyphenols. Other impacts of crop sequence were slightly higher concentrations in grain of P after pasture and Fe after canola. The bioavailability of grain Zn, as shown by the PA:Zn and Ca × PA:Zn molar ratios, mostly reflected Zn concentration and was low in all treatments. After milling, the PA:Zn molar ratio suggested low Zn bioavailability for flour from wheat grown with P fertiliser after canola or fallow. CONCLUSION: Crop management can affect the bioavailability of Zn in wheat grain, with practices leading to high yields potentially leading to low Zn bioavailability. Copyright © 2008 Society of Chemical Industry [source]


Molecular marker analysis of kernel size and shape in bread wheat

PLANT BREEDING, Issue 5 2003
B. B. Dholakia
Abstract The economic value of wheat grain is determined by the kernel morphology which is an important parameter for manufacturing different food products requiring specific grain characteristics. Although kernel size and shape have emerged as important breeding objectives, not much information is available about the number or location of associated gene(s)/quantitative trait loci. In the present study, a recombinant inbred line population of 106 plants (F7) was phenotyped for four traits, namely kernel length, width, weight and factor form density (FFD) and genotyped with different polymerase chain reaction-based markers. Transgressive segregants were observed for all the traits and genetic correlation studies showed positive correlations between the majority of the traits. The number of markers associated with each trait ranged from two to nine and the phenotypic contribution by an individual marker ranged from 3.3 to 16.6%. Many of the markers showed linkage to more than one trait. Strategies for improving the wheat grain quality traits and the utility of such markers in marker-assisted selection (MAS) efforts are discussed. [source]


The effects of differentiated water supply after anthesis and nitrogen fertilization on ,15N of wheat grain

RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 3 2010
Ivana Raimanová
The ,15N signature of plants integrates various processes in soil and plant. In this study, the effect of different water regimes applied during the period of grain growth of winter wheat on grain ,15N was examined in a 4-year field experiment. The treatments comprised water shortage (S), an ample water supply (W), and rain-fed crop (R). Zero fertilization (N0) and 200,kg,N.ha,1 in mineral fertilizer (N1) treatments were studied. The grain 15N was determined during grain growth and at maturity. The water regime, nitrogen application and year had a significant effect on mature grain ,15N (p,<,0.001). Water and nitrogen explained 54.6% of the variability of ,15N in the experiment, the year accounted for 10.7% and the interactions for another 19.6% of the total variability. The analysis of non-mature grain ,15N showed significant effects of N and year but not of water. Nitrogen fertilization reduced the ,15N of mature grain in years by 0.7,6.3, in comparison with N0 plants; the reduction was more pronounced under stress (average reduction by 4.1,) than under rain-fed (2.4,) and ample water supply (2.2,). Water stress decreased the grain ,15N in fertilized wheat, by 0.1,2.1, and 0.6,3.6, in experimental years, on average by 1.30, and 1.79, in comparison with the R and W water supply, respectively. The effect of water supply was not significant in non-fertilized wheat. A significant negative linear relationship between grain N concentration and ,15N in maturity or during the grain growth (R2,=,0.83, R2,=,0.76, respectively) was found. The observed sources of grain ,15N variability should be taken into consideration when analyzing and interpreting the data on the ,15N signature of plant material from field conditions. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Adapting wheat cultivars to resource conserving farming practices and human nutritional needs

ANNALS OF APPLIED BIOLOGY, Issue 4 2005
R M TRETHOWAN
Summary As farmers increasingly adopt resource conserving farming practices, there is a need for wheat cultivars that better adapt to the changing environment and the nutritional needs of people, particularly those living in developing countries. Improved adaptation to zero and minimum tillage, better water use efficiency, improved root health, durable resistance to foliar diseases and enhanced nutritional value of the grain are key selection criteria for plant breeders. Significant responses to selection for these constraints have been achieved at the International Maize and Wheat Improvement Center (CIMMYT), by selecting segregating populations and advanced lines in carefully managed tillage, moisture deficit and heat stressed environments, that correlate with key spring wheat growing environments globally. Root health has been improved through a combination of marker assisted selection and disease bioassays, and the nutritional value of wheat grain has been enhanced using genetic variation for high Fe and Zn grain content found among tetraploid wheat ancestral species. [source]


Response of multiple generations of cotton bollworm Helicoverpa armigera Hübner, feeding on spring wheat, to elevated CO2

JOURNAL OF APPLIED ENTOMOLOGY, Issue 1 2006
G. Wu
Abstract:, The growth, development and consumption of three successive generations of cotton bollworm, Helicoverpa armigera (Hübner), reared on milky grains of spring wheat grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers (OTCs) were examined. Decreases in protein, total amino acid, water and nitrogen content, and increases in total non-structure carbohydrates (TNCs) and ratio of TNC : nitrogen were found in wheat milky grains grown under elevated CO2 conditions. Changes in quality of wheat grains affected the growth, development and food utilization of H. armigera. Significantly longer larval lifespan for the third generation and lower pupal weight for all generations were observed in cotton bollworm fed on milky grains of spring wheat grown under elevated CO2 conditions. Bollworm fecundity was significantly decreased for the second and third generations under elevated CO2 levels. The consumption, frass per larva and relative consumption rate significantly increased in elevated CO2 compared with ambient CO2 conditions. However, the potential population consumption was significant reduced by elevated CO2 in the second and third generations. The results of this study indicate that elevated CO2 levels adversely affect grain quality, resulting in consistently increased consumption per larva for a longer period to produce less fecund bollworm through generations, suggesting that net damage of cotton bollworm on wheat will be less under elevated atmospheric CO2 levels because increased consumption is offset by slower development and reduced fecundity. [source]


REDUCED/OXIDIZED GLUTATHIONE INDEX AS A TOOL FOR FOOD MONITORITY OXIDATIVE STRESS DURING EXTRUSION COOKING

JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2001
H. ZIELINSKI
Reduced and oxidized glutathione was assayed in wheat, barley, rye, oats and buckwheat before and after extrusion cooking. The results obtained indicate that GSH/GSSG ratio was decreased from 1.91 and 10.72 for raw oat and buckwheat grains to the 1.13, 1.01, 1.10 and 4.72, 3.89, 3.89 for extruded material, respectively, in temperature used of 120, 160 and 200C. These results indicate that the oxidative stress is least developed during extrusion cooking of oat and buckwheat grains. Wheat and barley grains were more prone to oxidative damage, and the observed decrease of the ratio ranged from 6.84 and 4.89 (wheat cv. Almari and barley cv. Mobek, raw material) to the 1.89 and 2.07 (after extrusion cooking at 200C, respectively). No significance differences were found between two cultivars of wheat and barley being used in the experiment. The most decreased ratio up to five times was found in rye grain extrudates. The extrusion performed under barrel temperature profile of 80,100,120,120,120C caused significant decrease in GSH content when compared to raw material. The next higher barrel temperature profiles of 100,130,160,160,120C and 120,160,200,200,120C led to further GSH decrease in extruded wheat grains. In contrast, the two high temperature profiles did not [source]


RHEOLOGICAL AND SENSORY QUALITY OF READY-TO-BAKE CHAPATTI DURING FROZEN STORAGE

JOURNAL OF FOOD QUALITY, Issue 4 2009
D.N. YADAV
ABSTRACT The effect of prolonged frozen storage at ,18C, on the textural and sensory properties of ready-to-bake frozen chapatti (R-BFC) was evaluated. The R-BFC samples were prepared from normal- (control) and microwave-treated (18% moisture content for 80 s) wheat grains. Results showed that the extensibility of dough and maximum load for resistance increased gradually in both the samples during frozen storage; however, the increase was lesser in the treated ones. Chapattis prepared from both R-BFC samples exhibited higher hardness, cohesiveness, chewiness and lower springiness values during frozen storage. Microwave-treated R-BFC samples were rated as better retained in color, texture and overall acceptability scores as compared with control, up to 6 months of storage at ,18C. Thiamin and riboflavin contents were monitored during frozen storage and a loss of 12.0,14.5% in thiamin and 4,6% in riboflavin after 6 months of frozen storage was recorded. PRACTICAL APPLICATIONS During frozen storage, various physical, rheological and sensory changes occur in the food products, which determine the consumer's acceptability. The results of this study will help to establish quality of the frozen chapattis with respect to texture, color and aroma which will meet the consumer's acceptance. The protocol for the storage of frozen chapattis will help the industry to deliver the product of optimum quality. [source]


Sensory Profiles of Bread Made from Paired Samples of Organic and Conventionally Grown Wheat Grain

JOURNAL OF FOOD SCIENCE, Issue 4 2007
L.E. Annett
ABSTRACT:, The Canadian hard red spring wheat cultivar "Park" was grown in 2005 in Edmonton, AB, Canada on both conventionally and organically managed land, situated less than 1 km apart. Grains from the paired wheat samples were compared for cereal-grain-quality attributes. For sensory analysis, organically and conventionally produced wheat grains were milled into flour and baked into 60% whole wheat bread. Color, texture, taste, and aroma attributes of bread were compared using the sensory technique of descriptive analysis. Organic grain contained more wholemeal protein than conventional grain (P, 0.05), but both were greater than 14% protein, indicating excellent grain quality for yeast-leavened bread. Mixograph analysis revealed that conventional flour produced stronger bread dough than organic flour (P, 0.05). Visual observation confirmed these findings as conventional flour produced larger bread loaf volume. Fourteen sensory attributes were generated by the descriptive analysis panel. No differences were observed for flavor, aroma, or color attributes (P > 0.05), but the panel perceived the organic bread to be more "dense" in texture (P, 0.05) with smaller air cells in the appearance of the crumb (P, 0.05) than conventional bread. [source]


Silicon Suppresses Phytophthora Blight Development on Bell Pepper

JOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2010
Ronald D. French-Monar
Abstract The application of silicon (Si) reduces the intensity of diseases in several economically important crops. This study aimed at determining the potential of this element to decrease the symptoms of Phytophthora blight development on bell pepper, caused by Phytophthora capsici. Bell pepper plants (Sakata Hybrid X pp6115) were initially grown in plastic pots with substrate composed of 1 : 1 mixture of sterile fine sand and Fafard No. 2 peat mix amended with calcium silicate (+Si) or calcium carbonate (,Si). Six weeks later, plants were transplanted to new pots that contained the same +Si and ,Si substrate but were infested with finely ground wheat grains (1- to 2-mm diameter) colonized by two isolates of P. capsici, Cp30 (compatibility type A1) and Cp32 (compatibility type A2). At the end of the experiment, roots and stems from plants of each treatment were collected to determine Si concentration. The presence of lesions on crowns and stems and wilting of plants were monitored up to 9 days after transplanting (DAT). Data obtained were used to calculate the area under diseased plants progress curve (AUDPPC) and area under wilting plants progress curve (AUWPPC). Relative lesion extension (RLE) was obtained as the ratio of vertical lesion extension to stem length at 9 DAT. There was a 40% increase in the concentration of Si in the roots but not in the stems of bell pepper plants in the +Si treatment compared to the ,Si treatment. When comparing +Si to ,Si treatments, the AUDPPC was reduced by 15.4 and 37.5%, while AUWPPC was reduced by 29.1 and 33.3% in experiments 1 and 2, respectively. RLE values were reduced by 35% in the +Si treatment. Dry root weights increased by 23.7%, and stem weights were increased by 10.2% in the +Si treatment. Supplying Si to bell peppers roots can potentially reduce the severity of Phytophthora blight while enhancing plant development. [source]


Possibilities of using near infrared reflectance/transmittance spectroscopy for determination of polymeric protein in wheat

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2007
Éva Scholz
Abstract Possibilities of using near-infrared reflectance and near-infrared transmittance (NIR/NIT) spectroscopic techniques for detecting differences in amount and size distribution of polymeric proteins in wheat were investigated. To evaluate whether differences in polymeric protein due to genetic or environmental variations were detectable by NIR/NIT techniques, wheat materials of different background were used. Size-exclusion high-performance liquid chromatography was applied to detect variation in polymeric protein. Partial least squares regression gave high R2 values between many protein parameters and NIR/NIT spectra (particularly second-derivative spectra of NIR 1100,2500 nm region) of flours, while no such relationship was found for whole wheat grains. Most and highest correlations were found for total amount of extractable and unextractable proteins and monomer/polymer protein ratio. Some positive relationships were found between percentage of total unextractable polymeric protein in the total polymeric protein and percentage of large unextractable polymeric protein in the total large polymeric protein and NIR/NIT spectra. Thus, it was possible to detect differences in polymeric proteins with NIR/NIT techniques. The highest amount of positive correlations between NIR/NIT spectra and protein parameters was found to be due to environmental influences. Some correlations were found for breeding lines with a broad variation in gluten strength and polymeric protein composition, while a more homogeneous sample showed less correlation. Thereby, detection of variation in amount and size distribution of polymeric protein due to cultivar differences with NIR/NIT methods might be difficult. Copyright © 2007 Society of Chemical Industry [source]


Carbohydrate,ethanol transition in cereal grains under anoxia

NEW PHYTOLOGIST, Issue 3 2001
Lorenzo Guglielminetti
Summary ,,Cereal grains differ greatly in their reponses to anaerobiosis. Here, the in vivo conversion of carbohydrates to ethanol and CO2 under anoxia is reported for three cereal grains. ,,The conversion of glucose, fructose or sucrose to ethanol under anaerobic conditions was investigated in rice (Oryza sativa), barley (Hordeum vulgare) and wheat (Triticum aestivum) grains; alcohol dehydrogenase (EC 1.1.1.1) and pyruvate decarboxylase (EC 4.1.1.1) activities were also analysed under aerobic and anaerobic incubation. ,,Our data suggest that rice grains are able to produce ethanol under anoxia for the whole period of anoxic treatment, whereas barley and wheat grains can produce this terminal product of fermentation only during the first days of anaerobiosis. The level of enzymes involved in the fermentation pathway increases strongly under anoxic conditions in all three cereals. ,,Conversion of hexose to CO2 is nearly unaffected by anoxia in wheat, barley and rice, whereas only rice grains are able to degrade and utilize sucrose efficiently under anoxia. By contrast, wheat and barley do not utilize sucrose efficiently under anaerobic conditions. [source]