Proteins of high-yielding varieties of cashew (Anacardium occidentale)

Abstract

Salts (NaCl and KCl) at 250 mM and alkali (NaOH and KOH) at 50 mM concentrations extracted proteins from defatted cashew kernel flour to an extent of 54 to 68 per cent and 80 per cent respectively. Electrophoresis of salt extracted proteins both under native and denatured conditions did not reveal any varietal difference. Zn²⁺ at 1 mM concentration specifically precipitated the slow moving fraction of cashew proteins. Defatted cashew kernel flour from varieties M 76/1 and Tr.273.Bla had highest (73.14 µg/mg proteins) and lowest (35.98 µg/mg protein) lysine contents respectively. Extraction of protein from defatted kernel flour at pH 4 was almost one-tenth compared to pH 10. Lysine content in protein extracted at pH 10 was highest (63.3 µg/mg protein) in variety M 6/1 and lowest (35.12 µg/mg protein) in variety Tr.56.Bla.