Extraction of seabuckthorn seed protein by alkaline extraction and enzymatic hydrolysis

The seabuckthorn seed protein(SSP) was preprared from the seabuckthorn seed meal by two steps of alkaline extraction and enzymatic hydrolysis.The optimal parameters of alkaline extraction and acid precipitation were determined as follows: pH 10,ratio of seabuckthorn seed meal to water 1∶ 12,temperature 60 ℃,time 60 min.The optimum conditions of enzymatic hydrolysis were as follows: pH 8.5,dosage of Alcalase 240 U/g,ratio of residue after alkaline extraction to water 1∶ 10,temperature 60 ℃,time 60 min.The total extraction rate of seabuckthorn seed protein by alkaline extraction and enzymatic hydrolysis was 73.86%.Amino acid analysis of SSP indicated that the proportion of essential amino acid was more balanced than soybean protein isolate(SPI),and Met and Cys were the first limiting amino acid.