Technology for enzymatic preparation of rice foaming protein

Rice foaming protein (RFP) was produced using rice protein concentrate (RPC) as raw material. Response surface methodology (RSM) was used to optimize the preparation conditions of RFP, and the protein extraction rate, nitrogen soluble index (NSI), foaming property and foaming stability of RFP were measured. The optimized conditions for producing RFP were E/S (alcalase dosage/substrate dosage) 0.01943 U/g, reaction time 57 minutes, the ratio of stuff to liquid 1:7.27, temperature 60℃ and pH 7.5. Under the conditions, the foaming activity and foaming property of RFP were 131 mL and 162% respectively, and foaming stability kept 100% within 30 min. Protein extraction rate and protein purity were 34% and 88.05% respectively, and NSI kept above 90% when pH value was in the range of 2～12.