• The Korean Journal of Food And Nutrition
• /
• v.12 no.5
• /
• pp.490-495
• /
• 1999

A thermotolerant yeast Saccharomyces cerevisiae OE-16 was isolated from traditional Meju was investigated on their physiological characteristics and ethanol fermentation ability. Saccharomyces cerevisiae OE-16 were able to grow up to 45$^{\circ}C$ and 40% of glucose. Saccharomyces cerevisiae OE-16 was also resistant to 15% of KCl 1,200ppm of Pb2+, Hg2+ and 500ppm of potassium sorbate. From 20% glucose media Saccharomyces cerevisiae OE-16 produced 83.4g per liter of ethanol at 3$0^{\circ}C$ and 9.5g per liter of ethanol at 4$0^{\circ}C$ for 72 hours.

• The Korean Journal of Food And Nutrition
• /
• v.12 no.4
• /
• pp.339-343
• /
• 1999

A strain of gas-producing and volume-expanding yeast was isolated from Gochujang made in Sunchang by the traditional ways and was identified to be a Saccharomyces sp. This yeast was detected only in malt among the several ingrediants of Gochujang which means that the volume-expanding yeast comes into Gochujang at the time of making products through malt one of the major ingredients. However boiling of the malt-saccharified rice could not prevent the occurrence of the volume-expanding yeast in Gochuj-ang. This yeast was contained in the range of 5.67∼7.75 log10CFU/g in products made and aged between 1 monty and 3 year in Sunchang area.

• 한국균학회소식:학술대회논문집
• /
• 2014.10a
• /
• pp.23-23
• /
• 2014

There are many yeast strains have been discovered for industrial usage in global scale. In the point of view for the alcoholic fermentation performance and producing alcoholic beverage products, recently many countries have known about the importance of microorganisms as a valuable resource. Discovered with well performed yeasts have potential industrial application in diverse ways such as foods, beverages, cosmetics, pharmaceutical functions, and so on. In Korea, the yeast research has not been sufficiently performed especially for distilled spirits industry. As a result, not so little manufacturers use exotic yeasts from overseas even included the expensive royalties. Besides of those, to produce distilled spirits, many manufacturers do not use specialized yeast for distilled spirits. Distiller's characterized yeasts such as whisky, brandy, vodka, Japanese shochu and awamori, are all well-known industrialized. For decades, the distillers, except us, have selected, developed, and practised yeasts in accordance with distilled spirits characters. This study is about selection and industrial application of yeasts for the Korean pot distilled spirits. Finally 7 yeast strains were selected among over 1,000 yeasts from the traditional Nuruks, through the essential related tests based on brewing and distilling science. The selected yeasts show the appropriate characteristics of distilled spirits. The result of this study could help our distilled spirits industry be activated and stand independent from the exotic microbes.

• Microbiology and Biotechnology Letters
• /
• v.43 no.3
• /
• pp.241-248
• /
• 2015

Tuak is a traditional alcoholic beverage, one of the most widely known in the North Sumateran region of Indonesia. It is produced by a spontaneous fermentation process through the application of one or more several kinds of wood bark or root, called raru (Xylocorpus wood bark or a variety of forest mangosteen), into the sap water of sugar palm (Arenga pinnata) for 2−3 days. In this research, yeast that are potentially useful for ethanol production was isolated from Tuak and identified. Based on analysis of D1/D2 domain sequence of LSU (large subunit) rRNA genes, those isolated yeast strains, HT4, HT5, and HT10 were identified as Candida tropicalis. Fermentation test of these C. tropicalis isolates displayed an ability to produce 6.55% (v/v) and 4.58% ethanol at 30℃ and 42℃, respectively. These results indicated C. tropicalis isolates more rapidly utilize glucose and obtain higher levels of the production of ethanol at the higher temperature of 42℃ than S. cerevisiae, a common yeast used for bioethanol fermentation.

• Korean Journal of Food Science and Technology
• /
• v.37 no.1
• /
• pp.61-66
• /
• 2005

Korean traditional rice wine Takju and Yakju were manufactured using 2-step-brewing method. To investigate microflora involved in fermentation step, number of microorganisms, pH, titratable acidity, and alcohol contents of Takju and Yakju were measured. In Takju and Yakju, although not significantly, $1.1{\times}10^{8}$ and $2.0{\times}10^{6}\;CFU/mL$ lactic acid bacteria at initial stage of second fermentation decreased to $8.3{\times}10^{6}\;and\;1.0{\times}10^{4}\;CFU/mL$ at the end of second fermentation, respectively. For Takju, micrococci and yeast occupied 80 and 20% at initial stage of second fermentation, whereas bacteria and yeast occupied 35 and 65% at the end of second fermentation, respectively. Yeast occupied 88% throughout the second fermentation of Yakju. The main yeast isolated from both Takju and Yakju was identified as Saccharomyces cerevisiae using API 20C AUX kit. The yeast strain Candida magnoliae was also detected during fermentation of Takju and Yakju.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.27 no.4
• /
• pp.789-799
• /
• 1998

Literatures on microorganisms of traditional Korean nuruk published since 1945 were reviewed in this paper. Traditional Korean nuruk consists of raw barley and various grains. Traditional Korean nuruk consists of unbolied raw barely and various grains. They are ground to paste and moistened, and then naturally inoculated by airborne microorganisms. Therefore, many kinds of microorganisms such as fungi, yeast, and bacteria grwo in nuruk. Since 1945, new 14 species of Aspergillus and 9 species of Penicillium have been identified from traditional Korean nuruk. Total number of fungal species identified so far is now up to 38 species among 12 different genus. Among newly isolated fungal species, Aspergillus penicilloides and Penicillium, expansum showed not only high production rate of acid and amylase but also extreme stability of the enzyme at room temperature for 3 months. As examples of newly isolated yeast species, there are 5 species of Candida, 4 species of Hansenula, 1 species of Pichia and 1 species of Schizosaccharomyces. Total number of yeast species isolated so far is up to 18 species from different 8 genus. Newly isolated bacteria, were Bacillus pumilus, Lactobacillus casei and Leuconostoc mesenteroides.

• Journal of Microbiology and Biotechnology
• /
• v.10 no.6
• /
• pp.776-783
• /
• 2000

Various alcohol yeast strains have been isolated from main mashes of Korean traditional liquors, and their genetic diversities were previously reported [23]. In this study, the strain SHY111, showing the highest alcohol production, was tested for its fermentation and sporulation characteristics. Additionally, its haploid cells were isolated and tested for their growth and fermentation patterns. The strain was identified as Saccharomyces cerevisiae based on its morphological and physiological characteristics. The sequences of the ITS(internal transcribed spacer) and 5.8S rDNA regions of S. cerevisiae SHY111 were found to be identical to those of S. cerevisiae that was obtained from through the yeast genome project. The maximum fermentation ratio obtained by the strain SHY111 (96.7%) was almost the same as that by S. cerevisiae Balyun No. 1 (96.5%) that was a little higher than that by S. cerevisiae KCCM11215(95.8%). The strain was induced for sporulation in a sporulation liquid medium using log phase cells grown in different types of pre-sporulation media, and its haploid cells were obtained by spore dissection using a micromanipulator. The majority of the spores formed a small colony on a YPD agar plate, and the haploid yeast cells derived from the strain SHY111 showed a variety of growth and alcohol fermentation patterns. It was proposed that the fermentation patterns were related to their growth phenotypes in the most haploid strains, but possible not in some strains.

• KSBB Journal
• /
• v.14 no.4
• /
• pp.434-439
• /
• 1999

A wild yeast S-13 which has excellent killer toxin activity to gas-producing yeast of traditional Doenjang and Kochujang was selected among forty seven strains of Meju yeasts and identified as Hansenular capsulata S-13 by investigation of the morphological, cultural and physiological properties. The optimal conditions for the production of killer toxin were investigated. H. capsulata s-13 showed the higest killer toxin activities when it was cultured up to the late-log phase of 36 hr in YEPD medium (pH4.5) at $25^{\circ}C$ H. capsultara S-13 showed killer toxin activities to seven strains of industrial yeasts such as S. cerevisiae, C. veratilis and P. membranaefacieus.

• Korean Journal of Food Science and Technology
• /
• v.30 no.4
• /
• pp.941-947
• /
• 1998

We isolated seventy two lactic acid bacteria and two hundred yeast from traditional Andong sikhe. Microorganisms were isolate from 4 kinds of traditional Andong sikhe. The optimum temperature and pH for growth of sikhe yeast, No. SCS 5, was $30^{\circ}C$ and 4.5, respectively. SCS 5 produced $CO_2$ gas and 1.5% of alcohol in malt extract broth. SCS 5 was identified as S. cersvisiae from the observation of shape of vegetative reproduction, morphological and cultural chararteristics, fermentation and assimilation of carbon sources, and physiological characteristics.

• Korean Journal of Food Science and Technology
• /
• v.38 no.5
• /
• pp.659-667
• /
• 2006

In order to standardize the manufacturing processes of Hahyangju, a traditional Korean liquor, 29 yeast strains were isolated from traditional Nuruk. Strain N8 exhibited a particularly strong resistance to sugar. Strains HA2, HA3 and HA4 grew successfully in medium containing 10% ethanol. In comparison with the growth exhibited by these strains when grown in a yeast malt extract medium, the ethanol production rates for the three strains were 10.8%, 10.45%, and 10%, respectively in a yeast malt extract medium containing 25% glucose. Based on these results, HA3 was the strain selected for use in the manufacturing processes of Hahyangju and it was identified as a Saccharomyces cerevisiae strain with 97% ITS sequence similarity. The use of Saccharomyces cerevisiae HA3 causcd a decrease in the lactic acid content, acidity and growth of lactic acid bacteria in the fermentation mash. Following thc addition of Saccharomyces cerevisiae HA3 to the manufacturing process of Hahyangju, the second fermentation mash showed a 22% increase in the alcohol production rate associated with traditional fermentation; however, the amino acidity, pH and reducing sugar content showed little change. Sensory evaluation of Hahyangju fermented with S. cerevisiae HA3 also showed better scores than Hahyangju mashed by the traditional method.