Quality improvement and shelf-life enhancement of Philippine tapuy [rice wine]

Tapuy is an indigenous rice wine made by inoculating steamed rice with starter culture to undergo saccharification and fermentation. In some regions of the Philippines, this beverage is indispensable in important occasions such as wedding and fiesta. Major problems in traditional tapuy that limit its commercial value include turbidity, discoloration, souring, off-flavor and very short shelf-life. To improve the quality and shelf-life of rice wine, PhilRice has optimized the process parameters and ingredients, established the shelf-life and sensory profile and improved the packaging. The use of tap water resulted in wine with highest pH, alcohol content, alcoholic taste and calcium and magnesium contents. Although higher alcohol content and pH were produced with 3.0% starter, highest positive scores for color , alcoholic taste, bitterness and astringency were obtained from 1.0% starter. Wine fermented for two weeks obtained the highest over-all acceptability. Bacterial growth was observed for wine pasteurized for 5,10 and 20 minutes but none for 30 minutes. Physicochemical and sensory properties of wine aged for different periods did not differ significantly but the lowest off-odor and off-flavor scores were obtained from one-month aging. Addition of 0.5% activated charcoal best reduced color intensity and turbidity than samples treated with other clarifying agents. After optimization, the production process involved utilization of tap water and 1.0% starter culture, two-week fermentation, a 30-minute pasteurization and one-month aging and addition of 0.5% activated charcoal. Sensory profiling described PhilRice tapuy as a clear, full-bodied wine with luxurious alcoholic flavor, moderate sweetness and lingering finish. Frosted bottle with elegant label and paper bag were used as primary and secondary packaging, respectively and the product was still acceptable even after ten months of storage. The success in improving the quality and extending the shelf-life of rice wine enhanced its market potential, prompting the regular production and commercialization of PhilRice tapuy.