Preparation of protein from high temperature rapeseed meal

Protein was extracted from high temperature rapeseed meal by the combined method of enzyme method and alkali extraction.The optimum conditions were determined as follows: enzymolysis pH 7.0,temperature 50℃,ratio of material to liquid 1∶20,enzyme dosage 2.5%,reaction time 3 h;aqueous alkali pH 10.0,temperature 55℃,time 2 h,ratio of material to liquid 1∶12.Under the optimal conditions,the extraction rate of rapeseed protein was 71.63%.The extract was precipitated at isoelectric points of rapeseed protein(pH 4.0),and then decolorized by 70% ethanol to obtain the rapeseed protein with light-gray.The yield of rapeseed protein was 9.3%.The removal rate of tannin,phytic acid and glucosinolate was 56.65%,62.77% and 93.66%,respectively.