Advances in genomics have expedited the improvement of several agriculturally important crops but similar efforts in wheat (Triticum spp.) have been more challenging. This is largely owing to the size and complexity of the wheat genome1, and the lack of genome-assembly data for multiple wheat lines2,3. Here we generated ten chromosome pseudomolecule and five scaffold assemblies of hexaploid wheat to explore the genomic diversity among wheat lines from global breeding programs. Comparative analysis revealed extensive structural rearrangements, introgressions from wild relatives and differences in gene content resulting from complex breeding histories aimed at improving adaptation to diverse environments, grain yield and quality, and resistance to stresses4,5. We provide examples outlining the utility of these genomes, including a detailed multi-genome-derived nucleotide-binding leucine-rich repeat protein repertoire involved in disease resistance and the characterization of Sm16, a gene associated with insect resistance. These genome assemblies will provide a basis for functional gene discovery and breeding to deliver the next generation of modern wheat cultivars.

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A new fractionation procedure based on differential solubility was applied to wheat flour proteins to evaluate the relationship between protein fractions and functionality for breadmaking. Flour was initially extracted with 50% 1‐propanol. Monomeric proteins (mainly gliadins) and soluble glutenin contained in the 50% propanol soluble extract were fractionated by selective precipitation of the glutenin by increasing the concentration of 1‐propanol to 70%; monomeric proteins remain in the supernatant. Insoluble glutenin in the 50% propanol insoluble residue was extracted using 50% 1‐propanol containing 1% dithiothreitol (DTT) at 60°C. Protein in the final residue was extracted using SDS with or without DTT. It comprised mainly Glu‐1D high molecular weight glutenin subunits and nongluten polypeptides. For seven Canadian cultivars of diverse breadmaking quality, there was relatively little variation in the percentage of flour protein corresponding to monomeric proteins (48–52%) and residue protein (14–18%). In contrast, intercultivar variation in soluble and insoluble glutenin was substantial, with contents of 10–20% and 12–28% of flour protein, respectively. Soluble and insoluble glutenin were also highly correlated with physical dough properties, accounting for 83–95% of the variation of individual dough rheological parameters (except dough extensibility), and ≈ 74% of the variation in loaf volume. In contrast, monomeric and residue protein fractions were poorly associated with breadmaking quality. However, among the four protein fractions, only residue protein was significantly correlated (r = ‐0.79) with dough extensibility. The flour sample with the highest and lowest concentrations of insoluble and soluble glutenin, respectively, as well as marginally the lowest concentrations of monomeric and residue proteins was Glenlea, a cultivar of the Canada Western Extra Strong Red Spring wheat class which characteristically possesses distinctly strong dough mixing properties.

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Time/temperature integrators (TTI) have a potential for monitoring time-temperature history of perishable foods, including dairy products. To correlate the end of shelf life of dairy products with different TTI's, kinetic data for growth of a dairy spoilage microorganism was obtained. Both Arrhenius and square root equations were used to model the growth of Pseudomonusfrugii. A significant negative histoty effect was observed for P. fragi growth rate whereas history effect was positive on the lag phase, under certain nonisothermal conditions. A correlation scheme -of P. frugi growth was developed with the TI'I response. The application of TIT's for dairy products is feasible despite the history effects.

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Durum wheat samples (three varieties), milled to yield straight‐grade and patent flours, were processed into YANs. CWHWS and CWRS flours, customarily employed to make noodles, were included for comparative purposes. Uniaxial stress relaxation parameters, %SR, K1 and K2, derived from Peleg's model, were determined for all cooked noodles. Analysis of variance indicated a significant durum sample effect (P < 0.0001) on all three parameters. Significant differences (P = 0.05) were observed among all three CWHWS parameters and the durum flour samples, but not for CWRS. Significant correlations were detected among the three stress relaxation parameters and empirical texture measurements: RTC, REC and MCS. Flour yield exhibited a significant effect (P = 0.05) on %SR, K1 and K2, which was not detected using the empirical texture measurements. The uniaxial stress relaxation test provides a complementary, discriminating method for YAN texture measurement. PRACTICAL APPLICATIONS This describes the use of uniaxial compression to characterize and discriminate Asian noodle quality texture parameters on the basis of rheological principles. It demonstrates the discriminatory power of three parameters to discern similar noodle flour sources. The technique and parameters are simple to calculate and are well correlated with traditional empirical texture measurements.

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