The Influence of Autoclaving Soybean Oil Meal on the Availability of Cystine and Methionine for the Chick

Abstract

The nutritive value of the proteins of raw soybean oil meal, as determined by total gain in weight and gain per gram of protein consumed by chicks, was increased by autoclaving the meal at 100°C., 110 C., or 120°C. for 30 minutes. The protein nutritive values were lower when soybean oil meal was autoclaved at 130°C. for 30 or 60 minutes than when it was autoclaved at 100°–120°C. The availability for growing chicks of the methionine and cystine or the organic sulfur in soybean oil meal was increased by autoclaving the raw meal. The availability of the methionine and cystine or the organic sulfur was not as great when the meals were autoclaved at temperatures above 120°C. as it was when the meals were autoclaved at 100°C., 110°C., or 120°C. Added methionine increased the growth and feed efficiency on all diets. The addition of 0.2% dlmethionine to the basal diet increased the retention by the growing chick of the methionine originally in the unsupplemented diet. The methionine of the soybean oil meal was retained to a much greater extent than the cystine.