Optimization of purification process of macadamia nut protein isolate with enzyme method and analysis of its functional properties
In order to obtain macadamia nut protein powder with high purity,single factor and orthogonal experiments were used to determine the optimal conditions for purification of macadamia nut protein powder by glucoamylase with low purity macadamia nut protein powder as material.Pilot production(macadamia nut kernel—pressing—crushing—defatted macadamia nut cake powder—adding water and grinding—alkaline solution and acid precipitation—enzymatic hydrolysis purification—spray drying—purified protein powder)was practiced under the optimal process conditions.The solubility,emulsification,water-holding and oil-absorption capacities of the purified protein powder were determined,and the amino acid composition and content of the protein powder before and after purification were compared.The results showed that the optimal purification conditions for macadamia nut protein were as follows:enzyme dosage 100 U/g,enzyme hydrolysis temperature 55 ℃,enzyme hydrolysis time 90 min,and material-liquid ratio 1∶8.Under the optimal conditions,the pilot production showed that the protein content of the purified protein powder was 76.87％,the protein yield was 32.56％,and the protein extraction rate was 94.81％.The solubility of the purified protein powder was the smallest at pH 5.0,and the emulsification was the lowest,the water-holding and oil-absorption capacities reached the maximum value at 60 ℃.The amino acid composition of the purified protein powder was rich in 7 essential amino acids,and the total amino acid amount was 65.17 g/100 g,which was higher than that of the pre-purification.In conclusion,the purified protein powder of macadamia nut has good quality and functional properties.
NETL
NSTL
万方数据
