• 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.

• Food Science and Biotechnology
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• 제17권3호
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• pp.558-563
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• 2008

To prevent weakly flocculating characters of bottom brewing yeast during first fermentation, various technical investigations were carried out using strain of Saccharomyces cerevisiae. It appeared that the propagation at $10^{\circ}C$ promoted the molecular structure and biochemical composition of cell wall in favor of flocculation. The yeast grown at $20^{\circ}C$ by addition of zinc ion also had a stimulating effect on flocculation behavior during first fermentation cycle. The zinc ion did not influence directly on the changes of cell wall in favor of stronger flocculence. The increased fermentation activity of yeast due to addition zinc ion was rather responsible for the intensified flocculation capacity. It was concluded that the weakly flocculating characters of bottom brewing yeast during first fermentation can be solved by using yeast propagated at $10^{\circ}C$ or by means of yeast by addition of zinc ion during propagation.

• 한국미생물·생명공학회지
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• 제3권1호
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• pp.35-39
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• 1975

시판 정제 amylase 효소제를 이용하여 탁주양조때 탁주의 특징인 산미를 부여하기 위하여 유산균 Lactobacillus bulgaricus를 첨가하여 검토한 결양 1) L. bulgaricus의 생육 적온인 45$^{\circ}C$에서 8시간과 16시간 유산발효시킨 후에 효모를 첨가하여 만든 탁주류의 산도는 11.6과 13.9로서 너무 과양의 산이 생성되므로 탁간무로서는 불적당하었다. 2) 탁주류의 제조에서 유산난을 효모와 함께 3$0^{\circ}C$에서 접종하여 발효시킴으로서 산도8, 정도 12 vol%의 적당한 탁주류를 얻을 수 있었다. 3) 정제효소제와 유산균을 이용하여 탁주를 제조할때는 유산어과 효모의 동시접종에 앞서 당화효업의 작용최적온도에서 6시개동안정도 당화시킴이 합리적이다.

• 미생물학회지
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• 제8권2호
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• pp.53-64
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• 1970

In order to study ecology of microorganisms during Takju brewing, microflora changes were examined fromm the start to the sixth day of Takju fermentation in 24 hours intervals. Takju made from rice, flour and dried sweet potato in a liter volume open container at the laboratory and a sanple of Takju brewing factory were studied for their microflora and their changes during fermentationl together with a sample of Kokja. Results obtained were as follows ; 1. The followings were the identified microorganisms in Kokja. The molds ; Absidia spinosa, Aspergillus parasiticus. The yeasts ; Candida melinii, Candida Solani, Hansenula anomala. The bacteria ; Luctobacillus casei, Leuconostoc mesenteroides, Bacillus subtilis, Bacillus pumilus. 2. Torulopsis inconspicua, Lactobacillus casei, Leuconotoc mesenteroides, Bacillus subtilis, Bacillus pumilus were isolated from main mash of laboratory-made Takju samples. The yeast, Torupsis inconspicua which was not present in Kokja and, probably of a contaminant yeast, dominated the yeast flora of Takju mash of rice, flour and sweet potato of labotatory brewing. The laboratory brewing lost also always showed large population of lactic acid bacteria flora. 3. None of the wild yeasts which were present in Kokja appeared in Takju mashes. The Kokja appears to be of no use as the yeast source for Takju fermentation. Also the Kokja appears to be of not so effective amylolytic and proteolytic enzyme sources considering the microflora characteristics. Probably the major role of Kokja in Takju fermentation may be to contribute in taste formation. 4. Inoculation of Sacharomyces cerevisiae into the mash to the level of $10^7$ ml at the start of fermentation greatly changed the ecological aspects eliminating conditions of rather slow rising of natural contaminant yeast populaiton and fermentation which might give rise to prosperity of lactic acid and Bacillus bacteria that would be avoidable. 5. Examination of microflora of the large factory scale Takju fermentation showed the quite similar pattern of microflora and their changes to that of the cultured yeast-inoculated laboratory batch Takju fermentation. The cultured yeast dominated as the only predominant microflora, and the lactic acid bacteria flora were completely suppressed and aerobic bacteria, greatly. Probably this may be the regular microflora pattern of normal Takju fermentation. The role of lactic acid bacteria and aerobic bacteria in Takju fermentation may not be clear yet from this experiment alone.

• 한국식생활문화학회지
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• 제5권3호
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• pp.349-359
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• 1990

This study was carried out to understand and analyze the cooking and processing methods presented in CHE MIN YO SUL, Chinese books of husbandary was written in sixth century. This book was composed of two parts-part I is Agricultural production and part II is product-Utilization. Especially, wines and yeast(NU RUK) written in part II were studied at this study paper. Most of yeast was made of barley and wheat. These materials had been prepared as raw, steamed, and roasted state by proper ratio with kinds of yeast and then fermented as dough state. Occasionally, various kinds of soup made from cocklebur, leaves of mulberry tree, wormwood etc. put into yeast dough. Yeast doughs were shaped round and square with or without hole in the center, made in July of the lunar calendar and fermented for 3 or 4 weeks. There were 43 kinds of wines in this book. Most of them were made of all kinds of cereals grown at that time-rice, waxy rice, millet, waxy millet etc. These cereals had been steaming or cooking gruel with grain or powder state and then fermented with yeast. These wines were prepared by single or double brewing methods and the kinds of double brewing wines were more than single brewing wines by two times. There were none of wines made from fruit and distilled wines. Generally, single brewing wines were not made in Apr., Nov., Dec., of the lunar calendar and double brewing wines were not made in Aug., Oct., Nov., of the lunar calendar. And ripenning periods of wine brewing were various, from 1 day to 7 months for single brewing, from 2 days to 8 months for double brewing.

• 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.

• 한국산학기술학회논문지
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• 제20권11호
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• pp.376-385
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• 2019

본 연구는 쌀 맥주에 적합한 양조용 효모를 우리나라의 전통 누룩에서 분리 동정하고, 분리된 효모에 대한 쌀 맥주의 양조 적성을 파악하고자 하는데 그 목적이 있다. 6개월간의 연구 결과, 전통 누룩에서 선발된 4종의 양조용 효모는 이화학적 데이터 측면(pH, 당도, 알코올)에서 상업용 양조용 효모와 유사한 정상적인 발효 패턴을 보였으며 상업용 양조용 효모 보다 더 높은 활력을 보였다. 또 한편으로, 쌀 맥주의 아로마 성분 중에 특히 맥주의 아로마를 나타내는 고급 알코올과 에스터 농도는 각각 78.4로 부터 106.5 ppm 그리고 15.1부터 29.3 ppm을 나타내어 일반적으로 맥주에서 나타나는 농도를 나타내었다. 특히 Saccharomyces cerevisiae(KCCM 90313)는 상업용 효모에 의해 제조된 쌀 맥주에서 보다 유의적으로 더 높은 고급 알코올 농도와 에스터 농도를 보여주었기 때문에 쌀맥주의 아로마에 대한 긍정적인 효과가 있을 것으로 판단된다. 결론적으로, 전통 누룩에서 분리 동정한 4종의 효모들은 쌀 맥주의 제조에 적합한 것으로 판단되며, 특히 S. cerevisiae (KCCM 90313) 효모는 우수한 효모 활성과 아로마 생성능을 보여 주었으므로 향후 쌀 맥주 제조에서의 응용 가능성을 보였다.

• 한국미생물·생명공학회지
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• 제26권1호
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• pp.50-54
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• 1998

청주가 가지고 있는 향기는 청주의 품질을 결정하는 요인 중의 하나이다. 청주의 향기는 발효과정 중 주로 효모에 의해서 발생하는 것으로 알려지고 있고, ethyl caproate는 향기성분 중의 하나로 esterase가 생성에 관여하고 있는 효소의 하나로 보고되었다. 반면 청주 제조에 사용되는 청주효모와 코지균은 ethyl caproate의 생성과 분해 활성을 가진 esterase를 생산하는 것으로 보고되었다. 본 연구에서는 청주 제조 중 발생하는 ethyl Caproate의 생성에 미치는 청주효모와 코지균이 가지고 있는 esterase들의 영향을 알아보기 위하여 코지균과 청주효모의 생장 중 발생하는 ethyl caproate 합성과 분해에 관련하고 있는 esterase들의 활성 변화에 대하여 알아보았다. 청주효모가 가지고 있는 ethyl caproate 합성 esterase는 caproate에 의해서 유포되고, 분해 esterase는 ethyl caproate에 의해서 유도되지만 caproate에 의해서 저해되는 것으로 나타났다. 코지균의 ethyl caproate합성과 분해 esterase활성은 균체의 성장에 비례하여 증가하였으나 ethyl caproate 생성의 기질이 되는 caproate와 ethanol이 활성에 영향을 미치지 못하는 것으로 나타났다. 또한 코지균의 배양액에서 ethyl caproate 합성 esterase의 활성이 측정됨에도 불구하고 0.01 ppm까지 ethyl caproate를 검출할 수 있는 분석조건 하에서 배지 중의 ethyl caproate는 검출되지 않았다. 본 실험의 결과를 고려한다면 청주의 제조과정 중 생성되는 ethyl caproate는 코지균의 esterase에 의해서는 거의 생성되지 않고 당화과정 후 첨가되는 청주효모가 주로 생성하는 것으로 확인되었다. 또한 청주효모의 증식과정 중에는 효모의 생장과 더불어 ethanol이 생성되어 코지균의 생장을 억제한다. 따라서 청주제조 중 생성되는 ethyl caproate는 청주효모의 esterase에 의해 생산된 것으로 사료된다.

• 동아시아식생활학회지
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• 제1권2호
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• pp.133-149
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• 1991

The contents of“Joo-chan”consist of eighty two items about alcoholics, a number of side dishes and soybean sauces. Interpreted content was classified and analyzed. Selected 52 items among those brewages, artless-brewing alcoholics, were distributed into 6 large patterns. The materials used for brewing artless alcoholics were regular rice, waxy rice, wheat and yeast(NURUK). Six patterns, grounded on these materials, were set one thing to another and analyzed.

• 동아시아식생활학회지
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• 제8권4호
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• pp.345-359
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• 1998

The contents of 6 classical records consist of 208 items about alcoholics and a number of side dishes; 44 items in YuckJooBangmoon, 82 items in Joochan, 19 items in the "sulbitnunbup", 24 items in Kyuhapchongsu from Korea university, and 39 items in Kyuhapchongsu. Interpreted content was classified and analyzed. Selected 27 items among those brewages, artless-brewing alcoholics, were distributed into 4 large patterns. The materials used for brewing artless alcoholics were regular rice, and yeast (NURUK) Four patterns, grounded on these materials, were set one thing to another and analyzed. analyzed.