Effect of degree of hydrolysis on the functional properties of some oilseed proteins

Abstract

Hydrolyzing soybean, sesame, and ricebran meals with papain and bromelain enzymes under previously determined optimum conditions was accomplished. Aliquots were withdrawn from the bulk hydrolysates at different time intervals to determine the rate of enzymatic degradation, as well as the degree of hydrolysis of the hydrolysates at different time, intervals. Twelve hydrolysates were then chosen with low and high degree of hydrolysis. They also represented hydrolysates from the three substrates hydrolysed with the two enzymes used. Some functional properties of the twelve hydrolysates were examined and then an attempt to correlate the functional properties with the degree of hydrolysis was done. The investigated functional properties included: wettability, dispersibility, flowability, bulk density, nitrogen solubility index, water absorption capacity, oil holding capacity, gelation, thermostability, emulsifying capacity and foam stability. Results showed a direct relation between increasing degree of hydrolysis and nitrogen solubility and dispersibility. Wettability, flowability and emulsifying capacity gave better results with low degree of hydrolysis.