SCREENING OF GAMMA-ORYANOL CONTENT FROM THAI RICE BRAN WATER EXTRACTS FOR DEVELOPMENT OF A COLD DRINK PRODUCT

Abstract

This study aimed to quantify gamma oryzanol in rice bran water extracts and develop a cold drink product containing rice bran with the highest content of gamma oryzanol. Thai rice bran of four varieties including Riceberry, Black glutinous, Mali Nil and Sung Yod were extracted with distilled water. Black glutinous rice was found to have the highest yield of 33 w/w. Water extracts from the four varieties (200 µg/ml) were quantified for gamma oryzanol. Riceberry extract contained the highest amount of gamma oryzanol (3.38 g/100 g dry weight), followed by Black glutinous extract (2.92 g/100 gDW), Mali Nil extract (2.15 g/100 gDW) and Sung Yod extract (1.36 g/100 gDW). Therefore, Riceberry rice bran was selected to be developed into cold drink products. The study on sensory characteristics of 50 subjects using the Hedonic-9 scale test was performed. The study was divided into two phases. In the first preliminary phase, grain recipes were found to show positive feedback, while rice bran formulations were less popular than grain formulations. Hence, the cold drink formulation containing both grain and rice bran was developed in the second phase. The cold drink formulations were prepared using different weight ratios. The result showed that the most preferred score was formula with 2 g of rice bran mixed with 1 g of grain (5.28 ± 1.95).