Application of aromatic red rice bran to rice wine brewing: Studies on red rice wine brewing (Part 2)

Abstract

Rice wines were made from various kinds of rice and/or rice brans. The aromatic red rice wine made from unpolished aromatic red rice ( Oryza sativa var. Indica, Tapol), having a wine-like fruity aroma and sour taste, showed the highest quality, while rice wine made from polished aromatic red rice showed a lower quality in an organoleptic test and gas chromatographic analysis. Rice wines made from the bran of aromatic red rice and red rice, the waste product of the polishing process in Sekihan cooking, contained 2.5 times greater amounts of higher alcohols and 3.5–5.0 times greater amounts of volatile esters than rice wines made from the bran of glutinous and nonglutinous rices. Thus, the bran fraction of aromatic red rice was essential for the formation of a ruby color and fruity aroma. Various amounts of aromatic red rice bran were mixed with polished aromatic red rice and also applied to rice wine brewing. Rice wine made from 10 g of bran and 21 g of polished aromatic red rice showed the best quality according to the organoleptic test and gas chromatographic analysis. The optimal ratio of bran to polished rice as a raw material for rice wine brewing was almost equal to that of native unpolished rice. Aromatic red rice bran was further mixed with polished glutinous rice or nonglutinous rice and applied to rice wine brewing. The resulting rice wines had the characteristic ruby color and fruity aroma, just the same as the aromatic red rice wine made from native unpolished aromatic red rice. Thus, not only native unpolished aromatic red rice, but also its bran, could be applied directly and economically to rice wine brewing without the need for any complicated process.