Chiang Mai Journal of Science

This study deals with the production of value-added product derived from rice bran oil processing by-products. The investigation was divided into two parts, Part I: subcritical  ater (SW) hydrolysis of deoiled rice bran and Part II: separation of y-oryzanol from rice bran oil soapstock. In Part I SW hydrolysis reaction was carried out in a closed batch reactor in which the effect of temperature in the range of 200-220  o C, reaction time of 10-30 min, raw material to water weight ratio of  1:5 and 2:5, were determined on the  of  protein, amino acid, reducing sugars, and antioxidant activity. The results in the present study suggested that subcritical water could be used to potentially hydrolyzedeoiled rice bran into more valuable products. The suitable condition for protein and amino acids production from deoiled rice bran by subcritical water hydrolysis was 1:5 at 30 min and hydrolysis temperature of 220  o C. At this condition, the protein: 130.17 mg/g rice bran, amino acid: 9.14 mg/g rice bran. In Part II, separation of y-oryzanol from rice bran oil soapstock was conducted following the selected processes from literatures. The processes involve saponification, dehydration, leaching and crystallization. The content of y-oryzanol was analyzed by using UV spectrophotometer. The selected processes were demonstrated as suitable means for separating  from soapstock obtained locally.