Pretreatment of cottonseed flakes with proteases and an amylase for higher oil yields

Abstract

The effect of enzymatic pretreatment of cottonseed flakes on oil extractability was studied. The enzymes investigated included bacterial protease (Bp), papain (Pa), savinase (S), termamyl (T), pectinase (Pe) and cellulase (C).The variables studied during the enzymatic hydrolysis experiments were: enzyme concentration, moisture: cottonseed flakes ratio, and time of hydrolysis. Enzymatic hydrolysis experiments were first carried out with a single enzyme, then with enzyme mixtures formulated according to the results of single enzyme treatments. Results were evaluated based on the relative increase in oil extractability, and some oil characteristics in comparison with untreated cottonseed flakes (control). Pretreatment with enzyme mixtures resulted in a relative increase in oil extractability that was higher than single enzyme pretreatment and the control. Statistical analysis showed a significant difference (at 5% level) between the control and all enzymatically treated oils as well as among different enzymatically treated oils. The relative increase in oil extractability due to pretreatment with enzyme mixtures were in the following order: S: Pe: Bp > S: P > S: C: Pe > S: Bp > S: T > S: C > S: Pa with values 44.9%, 38.9%, 37.1%, 34.9%, 30.1%, 28.9%, respectively. Enzymatic pretreatment of cottonseed flakes resulted in oils with fatty acid composition, acid value, iodine value and peroxide values that were generally comparable to the control.