Cereal Chem. 86(4):463-469The objective of this study was to investigate whether a narrow-bore column (NBC) (300 × 4.5 mm, i.d.) improved analyses of unreduced proteins in flour by size-exclusion HPLC (SE-HPLC) and subsequent evaluation of breadmaking quality of hard spring wheat flours. Total protein extracts and SDS buffer extractable and unextractable proteins were analyzed by SE-HPLC. NBC separated proteins in 10 min at a flow rate of 0.5 mL/min with similar resolution to a regular column (300 × 7.8 mm, i.d.) which took 30 min. SE-HPLC absorbance area (AA) data ob-tained from an NBC showed comparable or superior repeatability and correlations with flour breadmaking characteristics when compared with those of a regular column. AA values of total protein that were calculated by adding AA values of SDS extractable and unextractable proteins showed greater repeatability and correlations with quality characteristics than those of actual total protein extracts. The improvements including employment of an NBC in SE-HPLC provide enhancement of rapid quality evaluation and decreased consumption of hazardous organic solvents.

Achieving acceptable end‐use (milling and baking) quality is a fundamental objective of wheat (Triticum aestivum L.) breeding programs throughout the U.S. hard winter wheat region. Numerous analytical methods have been developed to measure quality. Few tools are available to assist in the decision‐making process when faced with a large number of parameters from comprehensive milling and baking tests. Our objective was to develop a relational database system for summarization and interpretation of wheat end‐use quality data from the USDA‐ARS Hard Winter Wheat Quality Laboratory. The database system uses a graphical interface with a series of “layouts” that require input from the user, guide the user to a successive layout, or provide a data report. The database system provides simultaneous assessment of multiple quality traits on a standardized scale, userspecified prioritization of end‐use quality traits for numerical and qualitative ratings of genotypes, tabulation of major quality deficiencies of genotypes, and summarization of quality ratings for a genotype across multiple nurseries. The database system has specific application to the hard winter wheat regional testing program; however, the basic principle and design could be readily extended to nursery‐based enduse quality testing programs in other wheat regions and market classes.

The accuracy of using near‐infrared spectroscopy (NIRS) for predicting 186 grain, milling, flour, dough, and breadmaking quality parameters of 100 hard red winter (HRW) and 98 hard red spring (HRS) wheat and flour samples was evaluated. NIRS shows the potential for predicting protein content, moisture content, and flour color b* values with accuracies suitable for process control (R2 > 0.97). Many other parameters were predicted with accuracies suitable for rough screening including test weight, average single kernel diameter and moisture content, SDS sedimentation volume, color a* values, total gluten content, mixograph, farinograph, and alveograph parameters, loaf volume, specific loaf volume, baking water absorption and mix time, gliadin and glutenin content, flour particle size, and the percentage of dark hard and vitreous kernels. Similar results were seen when analyzing data from either HRW or HRS wheat, and when predicting quality using spectra from either grain or flour. However, many attributes were correlated to protein content and this relationship influenced classification accuracies. When the influence of protein content was removed from the analyses, the only factors that could be predicted by NIRS with R2 > 0.70 were moisture content, test weight, flour color, free lipids, flour particle size, and the percentage of dark hard and vitreous kernels. Thus, NIRS can be used to predict many grain quality and functionality traits, but mainly because of the high correlations of these traits to protein content.

Various whole‐kernel, milling, flour, dough, and breadmaking quality parameters were compared between hard red winter (HRW) and hard red spring (HRS) wheat. From the 50 quality parameters evaluated, values of only nine quality characteristics were found to be similar for both classes. These were test weight, grain moisture content, kernel size, polyphenol oxidase content, average gluten index, insoluble polymeric protein (%), free nonpolar lipids, loaf volume potential, and mixograph tolerance. Some of the quality characteristics that had significantly higher levels in HRS than in HRW wheat samples included grain protein content, grain hardness, most milling and flour quality measurements, most dough physicochemical properties, and most baking characteristics. When HRW and HRS wheat samples were grouped to be within the same wheat protein content range (11.4–15.8%), the average value of many grain and breadmaking quality characteristics were similar for both wheat classes but significant differences still existed. Values that were higher for HRW wheat flour were color b*, free polar lipids content, falling number, and farinograph tolerance. Values that were higher for HRS wheat flour were geometric mean diameter, quantity of insoluble polymeric proteins and gliadins, mixograph mix time, alveograph configuration ratio, dough weight, crumb grain score, and SDS sedimentation volume. This research showed that the grain and flour quality of HRS wheat generally exceeds that of HRW wheat whether or not samples are grouped to include a similar protein content range.

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