The invention discloses a method for extracting
peanut oil and fat and
protein with an
ultrasonic assisted aqueous enzymatic method, belonging to the technical field of fine
processing of agricultural products and comprehensive utilization of by-products. The method comprises the following steps: after
grinding blanched peanuts with a dry method, adding water to adjust alkali for ultrasonic-assisted extraction, and digesting after adjusting alkali at the second time; low-speed centrifuging to obtain free oil I and
emulsion I, and high-speed centrifuging the
emulsion I to obtain free oil II and
emulsion II; causing the emulsion II to carry out complex
enzyme breaking to obtain demulsification oil I, and causing stubborn emulsion to carry out
ethanol-assisted breaking to obtain demulsification oil II; ultra-filtering and desalting
protein fluid, and then
spray drying to obtain peanut isolate
protein powder. Finally, the
extraction ratio of free oil is 83 percent, the
extraction ratio of total oil is 92 percent, the protein
recovery ratio is 91.6 percent, the peanut protein purity is 89 percent, and the breaking ratio of emulsion can achieve 97-98 percent. Compared with the traditional aqueous enzymatic method, the method has the advantages that the
extraction ratio of free oil is increased, the dosage of
enzyme is greatly reduced, the
residual oil ratio of emulsion is significantly reduced, and meanwhile, the peanut protein
powder with high purity and good functionality is obtained.