Heat stability of milk: influence of modifying sulphydryl-disulphide interactions on the heat coagulation time–pH profile

摘要: Addition of reducing agents such as 2-mercaptoethanol (2-ME), dithio-threitol and Na sulphite to milk markedly reduced its heat stability at pH values below 7·1. 2-ME reversibly destabilized or serum protein-free casein micelle dispersions promoted the release κ-casein-rich protein from micelles. Reduction either micelles β-lactoglobulin (β-lg) with subsequent blocking newly formed –SH groups N-ethylmaleimide irreversibly maximum minimum ratio in profile. disrupted κ-casein/β-lg complexes stripped κ-casein on heating. The caseinate systems were thus destabilized. KBrO 4 iodosobenzoate 5 HIM eliminated but region maximum. However, KIO 3 mm had a strong stabilizing effect throughout range 6·5–7·3.