• Food Science and Biotechnology
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• 제17권4호
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• pp.739-744
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• 2008

The method of yeast propagation has an influence on yeast physiology, fermentation ability, flocculation rate, and taste stability of beer. In order to find optimal conditions for propagation, several parameters were investigated in combinations. The bottom brewing yeast grown at $10^{\circ}C$ indicated that a higher flocculation capacity during the $1^{st}$ fermentation. However, the taste stability and the aroma profile were not affected by parameters of propagation investigated. The beer quality was rather affected by storage duration. In addition, a correlation between tasting and chemiluminescence was found at the beer, which was produced using bottom brewing yeast. The propagation at $10-25^{\circ}C$ with addition of zinc ion indicated the best condition to improve fermentation ability, flocculation rate, and filterability for bottom brewing yeast, whereas the propagation at $30^{\circ}C$ with addition of zinc ion showed the best condition to increase fermentation ability for top brewing yeasts.

• 미생물학회지
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• 제54권4호
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• pp.379-383
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• 2018

맥주는 가장 대중적인 알코올 발효주이지만 퓨린(purine) 함량이 높아 고요산혈증 및 통풍 발생과 연관이 있다고 알려져 있다. 본 연구에서는 맥주 발효 온도를 달리함으로써 맥주의 퓨린 함량을 낮출 수 있는지 알아보았다. 맥주 제조의 주된 발효법인 상면 발효와 하면 발효에서 주로 사용되는 $20^{\circ}C$와 $10^{\circ}C$ 온도에서 맥주를 발효한 후, 각각에서 대표적 퓨린 화합물인 adenine, guanine 그리고 xanthine들의 함량을 high performance liquid chromatography 방법으로 측정하였다. 그 결과, $10^{\circ}C$ 발효 맥주가 $20^{\circ}C$ 발효 맥주에 비해 총 퓨린 함량이 낮았으며, 특히 adenine의 함량이 의미있게 낮아져 있음을 확인하였다.

• 한국식품과학회지
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• 제49권1호
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• pp.35-43
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• 2017

시판되는 상면발효맥주 12종에 대하여 5개의 외관, 9개의 향, 6개의 향미, 4개의 입안감촉에 대한 묘사용어를 개발하였으며, 묘사분석을 실시하였다. 실제 상면발효 맥주의 주요 특성으로 알려진 다양한 과일향미, 쓴맛과 관련 향미 용어가 개발되어 향후 상면발효맥주의 관능검사에 주요 평가 용어로 활용이 가능하리라 여겨진다. 또한 가용성 고형분, 총산도, pH, 환원당, 쓴맛 정도(B.U.), 탁도, 색도, 아미노산 함량, 총페놀함량과 DPPH 라디칼 소거능의 12가지 이화학특성을 분석하였다. 관능특성 항목과 맥주의 중요 지표인 이화학 특성간의 상관분석을 통해 B.U., 총폴리페놀 함량, 총산도, 황색도, 가용성 고형분이 에일맥주의 주요 관능특성인 시트러스향, 파인애플향, 쓴맛과 높은 상관관계를 보임을 확인할 수 있었다. 향후 이러한 이화학적 분석 항목은 제품 개발 시 관능특성 분석과 더불어 주요 품질지표 항목으로 활용이 가능하리라 여겨진다.

• Nutrition Research and Practice
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• 제1권4호
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• pp.260-265
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• 2007

Preservation methods on the physiological and brewing technical characters in bottom and top brewing yeast strains were investigated. The preserved yeasts were reactivated after 24 months storage and grown up to stationary phase. The samples of filter paper storage indicated a higher cell growth and viability during propagation than those of nitrogen and lyophilization storage independent on propagation temperature. In addition, the filter paper storage demonstrated a faster absorption of free amino nitrogen and a highest level of higher aliphatic alcohols production during propagation than other preservation methods, which can be attributed to intensive cell growth during propagation. Moreover, the filter paper storage showed a faster accumulation for glycogen and trehalose during propagation, whereas, in particular, lyophilization storage noted a longer adaptation time regarding synthesis of glycogen and trehalose with delayed cell growth. In beer analysis, the filter paper storage formed an increased higher aliphatic alcohols than control. In conclusion, the preservation of filter paper affected positively on yeast growth, viability and beer quality independent on propagation temperature. In addition, in this study, it was obtained that the HICF and Helm-test can be involved as rapid methods for determination of flocculation capacity.