In this study, we aimed to develop a fermented green rice beverage with a unique flavor and physiological function activity. With glutinous green rice and rice nuruk as independent variables, we modeled the antioxidant characteristics and α-glucosidase, α-amylase inhibitory activity of glutinous green rice fermented beverage to verify its significance. The total flavonoid content and α-glucosidase inhibitory activity were selected as Quadratic models, and DPPH radical scavenging ability and α-amylase inhibitory activity were selected as linear models. For the sensory characteristics of glutinous green rice fermented beverage, sweetness, sourness, savory taste, bitterness, throat feel, nuruk scent, and overall preference increased in preference as the amount of glutinous green rice and rice nuruk increased, but significantly decreased after the center point (p<0.01). A blending ratio of 180.00 g of glutinous green rice and 400.00 g of rice nuruk had the highest preference among all the sensory items. Based on these results, we developed a green rice fermented beverage with unique flavor and physiological function activity of rice using glutinous green rice and rice nuruk, and the optimal blending ratio was determined to be 164.04 g of white rice, 195.96 g of glutinous green rice, and 414.61 g of rice nuruk.

Gamma-aminobutyric acid (GABA) is a functional component with physiological activity that helps to protect the liver from blood pressure reduction and alcohol damage, and is known to be widely distributed in various vegetables and fruits. In this study, a fermented rice syrup with enhanced GABA content was developed. The improved syrup was prepared by adding monosodium glutamate (MSG) to saccharified rice and using a complex of three types of lactic acid bacteria (Lactobacillus brevis, Lactobacillus plantarum, Leuconostoc mesenteroides ) with excellent GABA production ability. The physicochemical changes of the fermented rice syrup were measured, and the final pH of the product was 4.7 with a total water-soluble solid content of 22.1 °Brix. Of the dissolved solids, glucose (39.6 mg/mL) and maltose (12.7 mg/mL) were the main components, and it was confirmed that all MSG was converted to GABA. From the experiment, it was established that the rice syrup obtained from secondary fermentation of saccharified rice is suitable as a beverage base. The fermented saccharified rice syrup was differentiated from conventional rice fermented products which typically use yeast and acetic acid bacteria in the production process. The enhanced fermented rice syrup produced in this study was made using lactic acid bacteria in the fermentation and saccharified rice.