감의 활용가치를 높이고 기능성 발효음료를 개발하기 위한 기초연구를 하고자 대봉감(Diospyros kaki Thunberg cv. Daebong), 선사환(Diospyros kaki Thunberg cv. Sunsawhan), 흑시떫은감(Diospyros kaki Thunberg cv. Heuksi-Astringent), 흑시단감(Diospyros kaki Thunberg cv. Heuksi-Sweet)을 이용하여 단행복발효 공정으로 감식초를 제조하였다. 감주스의 수득량을 높이기 위해 0.4% pectinase를 4시간동안 처리 후, 종배양한 주모(Saccharomyces cerevisiae KCCM 11215)를 접종하였다. 알코올 발효 4일째 대봉감주스로부터 8.0±0.00%의 알코올이 생성되었으며, 선사환주스, 흑시떫은감주스, 흑시 단감주스는 대봉감주스에 비해 다소 지연되어 발효 8일이 경과하면서 각각 8.0±0.05%, 8.0±0.00%, 및 6.2±0.05%의 알코올이 생성되었다. 제조된 감와인의 알코올 함유량을 6.0%로 조정 후, 종배양한 종초(Acetobacter pasterianus A8)를 5% 부피비율로 접종하여 30℃에서 정치 발효시켜 2일 간격으로 시료를 채취하여 분석하였으며, 발효 24일에 총산은 대봉감식초가 5.78±0.05%, 선사환식초는 5.25±0.04%, 흑시떫은감식초는 4.76±0.04%, 흑시단감식초는 5.23±0.03%로 나타났다. 또한 감식초 에서 catechin, epigallocatechin gallate, epicatechin, epigallocatechin 등 각종 카테킨이 검출되었 으며, 발효단계에 따라 epigallocatechin gallate와 epicatechin gallate의 증가가 현저하였으며, epicatechin은 소멸되기도 하였다. 흑시떫은감식초의 유리 phenolics 함량은 초산발효 전 감와인에 비해 유의적으로 감소하여 566.2±23mg/L 수준이었고, 그외의 감식초에서는 감소하여 대봉감식초 277.0±15.6mg/L, 선사환식초 264.4±15.7mg/L, 흑시단감식초 263.0±18.6mg/L이 검출되었다. 품종 별 감식초의 DPPH 라디칼 소거활성은 시료에 함유되어 있는 유리 phenolics 함량에 비례하여 높았으며, 흑시떫은감식초 94.67±1.4%, 대봉감식초 47.28±1.07%, 흑시단감식초 46.98±1.3%, 선사환식초 37.22±1.25% 순으로 높은 것으로 나타났다. 이상의 연구결과로부터 몇몇 품종의 감식초 제조가 가능 하게 되었으며, 특히 흑시떫은감식초는 유리 phenolics 함량이 다른 감식초에 비해 2배 이상 높아 이에 따른 항산화활성도 우수하였다. 따라서 본 연구에서 개발된 감식초는 조리용은 물론 기능성 음료로서 이용이 가능할 것으로 생각된다.

In order to increase the utilization value of persimmon and to develop a functional fermented beverage, persimmon vinegar was produced by a single fermentation process using various kinds of varieties such as Daebonggam(Diospyros kaki Thunberg cv. Daebong), Sunsawhan(Diospyros kaki Thunberg cv. Sunsawhan), Heukshi-astringent(Diospyros kaki Thunberg cv. Heuksi-Astringent),and Heukshi-sweet(Diospyros kaki Thunberg cv. Heuksi-Sweet). To increase the gain of persimmon juice, 0.4% pectinase was applied, and fermented into wine by Saccharomyces cerevisiae KCCM 11215. On the 4th day of alcohol fermentation, 8.0±0.00% of alcohol was produced from DB juice. After 8 days of fermentation, 8.0±0.05%, 8.0±0.00%, and 6.20±0.05% Of alcohol was produced from SW juice, HA juice, and HS juice. After adjusting the alcohol content of the prepared persimmon wine to 6.0%, and Acetobacter pasterianus A8 were inoculated, the physicochemical properties of persimmon vinegar were investigated by fermentation. The alcohol content of persimmon leaves was adjusted to 6.0% and Acetobacter pasterianus A8 were inoculated at a volume ratio of 5% and subjected to stationary fermentation at 30℃ to collect samples at intervals of 2 days. On the 24th day of fermentation, the total acid value was 5.78% for DB wine, 5.25±0.04% for SW wine, 4.76±0.04% for HA wine and 5.23±0.03% for HS wine. In addition, Various catechins such as catechin, epigallocatechin gallate, epicatechin, and epigallocatechin were detected in persimmon vinegar, and the epigallocatechin gallate and epicatechin gallate increased significantly during the fermentation stage, and epicatechin sometimes was extinguished. The content of free phenolics in HA vinegar was 566.2±23 mg/L, which was significantly lower than that of pre-fermented wine. In other persimmon plants, DB was 277.0±15.6 mg/L, SW was 264.4±15.7 mg/L and HS was 263.0±18.6 mg/L. The antioxidant activity of persimmon vinegar was high in proportion to the content of free phenolics in the samples. HA 94.67±1.4%, DB 47.28±1.07%, HS 46.98±1.3% and SW was 37.22±1.25% in order. From the above results, it has become possible to produce persimmon vinegars of several varieties. Especially, the content of free phenolics in Heukshi-astringent persimmon vinegar was more than two times higher than that of persimmon vinegar. Therefore, persimmon vinegar developed in this study could be used as a functional drink as well as a cooking drink.

초록
 ABSTRACT
 서론
 재료 및 방법
  1 재료 및 시약
  2 종균배양
  3 감식초 제조
  4 감식초 제조 중 이화학적 특성
   4.1 pH
   4.2 산도
   4.3 알코올
   4.4 가용성 고형분
   4.5 색도
   4.6 유리당
   4.7 유기산
   4.8 카테킨
   4.9 유리 phenolics
   4.10 항산화 활성
 결과 및 고찰
  1 품종별 감식초 발효
   1.1 감주스의 수율과 당도
   1.2 알코올발효
   1.3 초산발효
  2 감식초 제조과정 중 이화학적 특성
   2.1 색도
   2.2 유리당
   2.3 유기산
   2.4 카테킨류
   2.5 유리 phenolics 함량 및 항산화활성
 감사의 글
 References

• 이윤주(경남과학기술대학교 식품과학부, Department of Food Science, Gyeongnam National University of Science and Technology) | Lee yun Ju
• 류재하(경남과학기술대학교 식품과학부, Department of Food Science, Gyeongnam National University of Science and Technology) | Rhyu Jae Ha
• 서원택(경남과학기술대학교 식품과학부, Department of Food Science, Gyeongnam National University of Science and Technology) | Weon Taek Seo Corresponding author