Protein Characterization and Amino Acid Profiles of Various Wheat Varieties and Their Effect on Pasting Properties of Starch

Abstract

The present study is to investigate amino acid compositions and protein characteristics of gluten extracted from different varieties of wheat and their influence on the pasting properties of starch. The starch and gluten are isolated separately from 12 wheat varieties categorized by grain hardness, i.e., hard (HW), medium hard (MHW), and soft (SW)with value ranged from 83 to 95, 72 to 80, and 17 to 29, respectively. Amino acid profiling reveals significant variations among the wheat varieties, with extraordinarily soft wheat (Ex‐SW) varieties exhibited higher levels of essential amino acid including methionine, phenylalanine, tryptophan, threonine, isoleucine, histidine, lysine, and valine. Protein fraction analysis indicates that gluten from HW varieties has a higher proportion of gliadin and lower glutenin content compared to MHW and Ex‐SW varieties. Furthermore, starch from Ex‐SW varieties possesses higher pasting parameters than MHW and HW varieties. Further, incorporation of gluten significantly reduced the pasting characteristics of starch. Flours with higher protein content demonstrate lower paste breakdown, highlighting the influence of protein content on viscoelastic properties. Furthermore, principal component analysis (PCA) reveals associations between specific amino acids and protein fractions with various pasting properties, highlighting the complex interplay between gluten composition and starch behavior.