ABSTRACTAn alkaline extraction procedure was used to produce protein and starch fractions from air‐classified high‐protein soft wheat flour. Optimum extraction was at pH 11.1 in 0.03N sodium hydroxide with a solvent‐to‐flour ratio of 6:1. After centrifugation, the alkaline extract was adjusted to pH 6.1 to yield a precipitate and a supernatant. Protein content (nitrogen × 5.7) of the isolates (dried precipitates) varied between 88 and 96, accounting for 64‐72 of the total protein. The ‘isolates had from. 1.7‐1.8g lysine and 3.6‐4.7g total sulfur amino acids per 16g of nitrogen. The isolates had minimum solubility of around 9 near pH 6; solubility was about’ 90 at pH 2.3 and 62‐93 at pH9.7. All isolates had good emulsifying activity (47‐98), emulsion stability (46‐97), and hydr
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