Yield, Quality and Shelf-life Responses of Three Varieties of Soybeans to Three Processing Temperatures Using the Vitagoat System of Soymilk Production

Three improved varieties of soybean, Anidaso, Nangbaar and Quarshie were used in the study to determine the effect of variation and processing temperature on the yield, quality and shelf-life of soymilk produced by the VitaGoat processing system. Two kilograms of each of the varieties were processed into soymilk at three temperatures of 110°C, 115°C and 120°C. The yield of each variety at the various temperature levels was measured by the total volume of the soymilk produced. Three samples of the soymilk from each variety were randomly selected for proximate analysis. Five samples were also randomly selected, kept at room temperature and monitored daily for three weeks to determine their shelf-life based on spoilage by coagulation. Nangbaar variety processed at a temperature of 110°C recorded the significantly highest soymilk yield and the least was recorded by Quarshie variety treated at a temperature of 120°C. Soymilk produced at 110°C was significantly (p<0.01) highest in protein content than at 115°C or 120°C. The combined effect of Anidaso and 110°C was significantly (p<0.01) highest in protein content than that of the other combinations. The soybean varieties did not significantly (p<0.01) influence the shelf-life of soymilk during the study. Soymilk produced at 120°C had significantly (p<0.01) longer in shelf-life than that of 110°C and 115°C. Quarshie at 120°C had significantly (p<0.01) longest in shelf-life than that of the other interactions. It was concluded that Anidaso at 110°C was rated the best among the varieties and processing temperature for producing high protein content soymilk.