| Summary: | 碩士 === 大葉大學 === 食品暨應用生物科技學系 === 107 === Black rice is a hybrid breeding indica rice variety via genomic selection of Tainung No. 67. After milling, the brown rice shows long-grain and purple color in appearance. Anthocyanin, a natural plant pigment, contained in bran not only represents the composition feature, but has antioxidant effect such as scavenging free radicals. Alcoholic beverages including brewed and reprocessed, were developed by using the black rice in this study. The functional components and antioxidant activity of the obtained products were analyzed and the results were as follows.
1. Three black rice wines products including brewed, distilled, and mixed with kaoliang (sorghum wine) were developed with alcohol concentration 10-12%, 35%, and 58%, respectively. Their manufacturing processes were established.
2. Black rice extract with anthocyanin concentration of 93.25 mg/L was prepared by immersing black rice in 60% edible alcohol and 5% citric acid at 60℃. This product was applicable to adjust alcohol and anthocyanin content of products.
3. Stability test showed anthocyanin in black rice extract degraded with increasing temperature. Only 38% of anthocyanin retained after treated at 60℃ for 24 hours; fortunately, only little change was observed for that of room temperature. In addition, no significant changes were found on visual observations.
4. Higher temperature environment test showed that color of brewed black rice wine changed drastically at 50℃(⊿E 25.84). ⊿a changed from positive to negative value when above 60℃, but ⊿b value changed slightly.
5. On DPPH free radical scavenging ability, 97% for black rice extract, 58% for brewed wine, and 48.5% for both distilled and kaoliang were observed. The reason possibly related to components contained in the products.
Key words: Black rice, Brewed wine, Distilled spirit, Anthocyanin, DPPH scavenging ability
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