Relationship of Protein Composition of Durum Wheat with Pasta Quality and the Effects of Processing and Cooking on These Proteins

Abstract

The protein components of semolinas from 12 durum wheat varieties differing widely in pasta quality were studied by solubility fractionation. Simple correlations between some pasta-quality parameters and the proportion of each protein fraction showed that the proportion of residue protein appeared to have a direct relationship with specific dough and gluten properties.The effects of processing (wet extrusion and drying), and of cooking, on the proteins from five varieties of durum wheat were investigated by protein solubility distribution, gel filtration chromatography on Sephadex G-200 and electrophoresis in sodium dodecylsulfate. Although processing changed both the protein solubility distribution and gel filtration properties, no significant changes occurred in the electrophoresis patterns of the fractions obtained by solubility fractionation.Cooking brought about insolubilization of the proteins in pasta. The electrophoretic patterns of the protein fractions obtained from the cooked sample only remotely resembled those from corresponding semolina and uncooked pasta fractions.The proportion of insoluble protein in cooked pasta appears to be related to cooked pasta tenderness index, suggesting that the greater the proportion of insoluble protein the firmer the product and the better the cooked quality.