The invention discloses a 
processing method for a low-allergenic soybean 
powder, belonging to a traditional 
soybean product processing technology. The 
processing method comprises the following steps:(1) soaking selected soybeans, then wiping 
moisture from soaked soybeans with a gauze, and placing wiped soybeans into a vacuum refrigerator; (2) laying frozen soybeans onto the gauze, and placing thegauze into an ultrasonic hot-
air dryer; (3) directly pulping dried soybeans, carrying out filtering with a filter screen, stewing obtained raw soybean milk in a stewing pot, carrying out continuous boiling, and adding 
alkaline protease; (4) conveying the soybean milk into a 
homogenizer for homogenization, and carrying out spray-
drying; and (5) irradiating obtained soybean 
powder with a pulsed 
ultraviolet light for sterilization so as to obtain the low-allergenic soybean 
powder. According to the invention, by combination of soybean vacuum freezing with an ultrasonic hot-
air drying technology and an 
ultraviolet pulse technology, various microorganisms in food and packaging are killed through instantaneous and high-intensity 
pulse light energy; immunoreactivity is reduced, and changing of aprotein structure and reduction of an 
IgE binding ability are promoted, so allergenicity of the soybeans is reduced; compared with traditional hot-
air drying, ultrasonic hot-
air drying needs shorter 
heating time, so allergenic substances in the soybeans are rapidly destroyed; and 
bacteria in the soybean powder grow more slowly than the 
bacteria in traditional soybean powder, so the 
shelf life of the soybean powder is prolonged.