Modification of peanut protein by high hydrostatic pressure combined with enzymatic method and its properties
In order to promote the deep processing and broader application of peanut protein,peanut protein was modified by high hydrostatic pressure combined with alkaline protease hydrolysis.The effects of hydrostatic pressure,pH,enzyme addition amount,enzymatic time and enzymatic temperature on the solubility of peanut protein were investigated by single factor experiment,then orthogonal experiment was used to optimize the modification process of peanut protein.The foaming property and foam stability,sulfhydryl and disulfide bond contents,and total reducing capacity of the co-modified peanut protein were determined.The results showed that the optimal co-modification conditions for peanut protein were hydrostatic pressure 300 MPa,1 g/100 mL alkaline protease(200 000 U/g)addition amount 3.0 mL(based on 100 mL peanut protein solution with mass fraction of 5%),pH 10,enzymatic temperature 50 ℃,and enzymatic time 60 min,and the protein solubility was(82.87±0.51)%under these conditions.The foaming property and foam stability,sulfhydryl group content,and total reducing capacity of co-modified peanut protein improved,while the disulfide bond content decreased.In conclusion,the combination of high hydrostatic pressure and enzymatic method can improve the physicochemical properties and functional properties of peanut protein,which facilitates the deep processing and broader application of peanut protein.