The objective of this research was to investigate the quality characteristics of the spirits by different distillation and filtrations. The contents of alcohol, total acids, and amino acids in rice mash were 15%, 0.25 g/100 mL, and 0.15 g/100 mL, respectively. The soluble content was 10°Brix, and pH was 4.6 in the rice mash. Lactic acid was the most prominent organic acid found in rice mash. The rice spirit distilled by a multi stage distiller showed the highest amounts of aroma compounds, such as fusel oil and esters. However, the filtration did not affect the amounts of total aroma compounds. It is suggested that a multi stage distiller may influence taste and flavor positively by enhancing the aroma and removing the impurities in rice spirits.Key words: rice spirits, distillation, filtrations, fusel oil, ester

This study examined the antioxidant capacities of apple peel, grape peel, and sweet potato peel. The antioxidant activities were evaluated using total phenolic contents, total flavonoids contents, DPPH radical scavenging activity, ABTS radical cation scavenging activity, FRAP reducing power, and ORAC assay. The total phenolic (7.76 μM quercetin equivalent/g peel) and total flavonoids (1.03 μM quercetin equivalent/g peel) contents in apple peel were significantly higher than in grape peel and sweet potato peel (P<0.05). The scavenging activities of DPPH and ABTS radicals of a 70% ethanol extract of apple peel was 3.2-4.6 and 2.8-5.4 times high than those of grape and sweet potato peel, respectively. In addition, the FRAP reducing power and ORAC assay of 70% ethanol extraction from apple peel were significantly higher than those of the other samples. Therefore, apple peel can be used efficiently as a natural antioxidant.

Houttuynia cordata Thunb is a famous traditional Chinese medicine. Also it has rich in functional and bioactive substances with outstanding immunopotentiation, anti-cancer, antimicrobial, and anti-aging effects. This study was evaluated water and 70% ethanol extracts of Houttuynia cordata Thunb using in vitro system antioxidant properties methods. The scavenging DPPH and ABTS radicals of 2 mg/mL 70% ethanol extract were 91.8 and 54.8%, respectively. Also, The FRAP assay of this showed increase in activity. In results, the antioxidant properties of 70% ethanol extract increased significantly compared to water extract(p < 0.05). Therefore, 70% ethanol extract of Houttuynia cordata Thunb may contribute to antioxidant property.

This study examined the physicochemical characteristics of mashing prepared using different Nuruks (traditional Nuruk, Nuruk added Aspergillus oryzae, Nuruk added Aspergillus kawachii, and Nuruk added Aspergillus oryzae and Aspergillus kawachii), and to obtain the basic data for Korean Cheongju production. The four different mashes were compared for their brewing characteristics and indicated a normal fermentation pattern. The Nuruk made from A. oryzae or A. kawachii showed higher fermentation ability than the other samples tested. In addition, the analyzed results of fermented mashing showed that the Nuruk made from A. oryzae or A. kawachii had a significantly higher aroma profile, such as higher alcohol and ester than the other samples tested, whereas the Nuruk made from a mixture of A. oryzae and A. kawachii had a much higher organic acid content. In conclusion, the Nuruk prepared using A. oryzae or A. kawachii had a positive effect on the complete fermentation and enhanced aroma compounds for Korean Cheongju production.