Main content area

Protein distributions among hard red winter wheat varieties as related to environment and baking quality

Huebner, F.R., Nelsen, T.C., Chung, O.K., Bietz, J.A.
Cereal chemistry 1997 v.74 no.2 pp. 123
winter wheat, durum wheat, cultivars, protein composition, baking quality, gliadin, glutenins, breadmaking, geographical variation, molecular weight, correlation, wheat protein, polypeptides, line differences, volume, flour, breads, Texas, Oklahoma, Colorado, Nebraska
Previous size-exclusion high-performance liquid chromatography (SE-HPLC) studies of hard red spring (HRS) wheat proteins reported correlations of amounts of certain gliadin and glutenin fractions with general score, a quality descriptor based on loaf volume, mixing time, and other parameters. We now extended these studies to 12 hard red winter (HRW) wheats, each grown at six Midwestern locations. Gliadin and reduced glutenin fractions were isolated and fractionated by SE-HPLC. Amounts of fractions corresponding to specific molecular weight (MW) ranges, determined by integrating peaks from SE-HPLC elution profiles, were statistically correlated with various baking quality parameters. Amounts of one fraction rich in gamma-gliadins correlated well with loaf volume; correlations were better than found previously for HRS wheats. Correlations adjusted for overall protein (partial correlations) were >0.5 for 10 of the 12 samples, and >0.84 for six samples when estimated among samples, among locations, among samples at each location, and among locations for each sample. Because gamma-gliadins appeared well correlated to loaf volume, the gliadin fraction was also analyzed by reversed-phase high-performance liquid chromatography (RP-HPLC), which provides better separations. Correlations of gamma-gliadin peak areas from RP-HPLC with loaf volume were then 0.93-0.99 for different varieties grown in different locations. Narrow-bore columns with shorter run times gave slightly higher correlations than did standard RP-HPLC columns. It is evident that both genetics and environment affect the relationship of quantitative protein distribution to loaf volume.