Quality, phenolic compound and antioxidant activity of wines from Sangyod rice grain, paddy and husk during fermentation

Abstract

The objective of this study was to utilize husk, byproduct from milling, and paddy of Sangyod rice that rich in bioactive compound to produce value added product as wine by reducing milling step of paddy. Quality changes, total phenolic content and antioxidant activity of wines from Sangyod rice grain, paddy and husk were monitored throughout the fermentation period. The acceptance of finished products from consumer drinking wine was also investigated. Alcohol content of three types of wine increased as the fermentation time increased. Paddy wine showed the fastest alcohol production following by rice grain and husk wine, respectively (P<0.05). Generally, total soluble solid and pH of wines decreases as the fermentation time increased. Yeast and mold increased throughout the fermentation time. As the fermentation time increased, total phenolic content and antioxidant activity including DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and metal chelating activity increased throughout the fermentation period (P<0.05) related to total phenolic content. Total phenolic content in three types of wines increased from 32-53 to 125-178 (mg GAE/ml). Generally, paddy wine possessed the highest total phenolic content and antioxidant activities when compared with rice grain and husk wine (P<0.05). From the sensory evaluation including appearance, odor, taste and overall liking, the scores of rice grain and paddy wines were moderate, while the lowest scores in all attributes was observed in husk wine (P<0.05). Rice grain, paddy and husk wines obtained were amber in color (L*=10.11-16.27, a*=8.07-14.91, b*=10.8-12.18). Thus, the changes of quality, total phenolic contents and antioxidant activity of wine during fermentation were governed by raw material used and fermentation time. Additionally, Sangyod rice grain and paddy could be used as potential raw material for wine production and the wines obtained could be served as potential drinks for health, since containing bioactive compound as antioxidant.