• 한국균학회지
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• 제20권3호
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• pp.269-272
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• 1992

이짚트, El-Minia시(市)의 공기중에서 208 효모들을 분리하였으며, 이들을 22개의 형태적 및 생리적인 특성을 이용하여 동정한 결과 7속 8중으로 나타났다. Rhodotorula rubra와 Cryptococcus Albidus은 가장 많이 발견되는 우점종들이였다. 이러한 효모들은 일반적으로 많이 발견되었으나, 다른 것들은 계적인 변화에 따라 다르게 나타났다. Rh. mucilaginosa, Saccharomyces Klayveri 및 Rh. avrantiaca는 또한 발견되었다. 이 연구의 결과, 효모의 프로라나 구성은 시간(주기) 고도 및 체취 지역에 따라 다련면을 보였다.

• Journal of Microbiology and Biotechnology
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• 제28권1호
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• pp.105-108
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• 2018

Beef was dry aged for 40-60 days under controlled environmental conditions in a refrigerated room with a relative humidity of 75%-80% and air-flow. To date, there is little information on the microbial diversity and characteristics of dry aged beef. In this study, we explored the effect of change in meat microorganisms on dry aged beef. Initially, the total bacteria and LAB were significantly increased for 50 days during all dry aging periods. There was an absence of representative foodborne pathogens as well as coliforms. Interestingly, fungi including yeast and mold that possess specific features were observed during the dry aging period. The 5.8S rRNA sequencing results showed that potentially harmful yeasts/molds (Candida sp., Cladosporium sp., Rhodotorula sp.) were present at the initial point of dry aging and they disappeared with increasing dry aging time. Interestingly, Penicillium camemberti and Debaryomyces hansenii used for cheese manufacturing were observed with an increase in the dry aging period. Taken together, our results showed that the change in microorganisms exerts an influence on the quality and safety of dry aged beef, and our study identified that fungi may play an important role in the palatability and flavor development of dry aged beef.

• 미생물학회지
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• 제22권1호
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• pp.1-18
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• 1984

1976年 3月부터 1977年 2月까지 滿 12個月동안 榮山江 汽水域 39個 場所로부터 採水한 156個 water sample로서 酵母의 季節的 分布와 度包配에 따른 이들 酵母의 分布型을 調査하였다. 酵母의 全體 平均値는 100ml당 52에서 487個의 生菌數를 보여주었고 가장 많은 個體數는 春季에 있었고 가장 적은 個體數는 夏季에 있었다. 14屬 83種에 해당하는 933個의 酵母와 한 種의 酵母樣 곰팡이가 分離되었는데 基中 Candida가 29%, Debaryomyces가 17.3%, Rhodotorula가 16%, Saccharomyces가 14%이었고 나머지 다른 屬들은 10%以內이었다. Debaryomyces hansenii와 Rhodotorula glutinis가 全水域에서는 물론 年中 優點種이었고 총 好氣性細菌集團의 크기, 陸水流入量, 그리고 몇가지 지형적 기후적 요소들이 汽水환경에서 酵母의 季節的 分布는 물론 種의 組成을 反映하는 같다. 酵母의 平均數, 種의 多樣性 特히 醱酵性 및 爲菌系形成 母酵들의 數는 감度가 감소함에 따라 增加한 反面 질산염 利用酵母들은 위와 相反된 경향을 보여주었는데 이는 汽水域에서 酵母의 分布型을 認識하는데 감度勾配가 바람직한 看破 요소로서 利用될 수 ㅣ있음을 시사하고 있다.

• 한국축산식품학회지
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• 제42권6호
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• pp.928-941
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• 2022

This study aimed to analyze the microbiological composition and sensory characterization of fermented sausage using strains isolated from Kimchi (GK1, Pediococcus pentosaceus SMFM2016-GK1; NK3, P. pentosaceus SMFM2016-NK3), Doenjang (D1, Debaryomyces hansenii SMFM2021-D1), and spontaneously fermented sausage (S8, D. hansenii SMFM2021-S8; S6, Penicillium nalgiovense SMFM2021-S6). The control was commercial starter culture. Nine treatments were applied [GD (GK1+D1), GS (GK1+S8), GDS (GK1+D1+S8), ND (NK3+D1), NS (NK3+S8), NDS (NK3+D1+S8), GND (GK1+NK3+D1), GNS (GK1+NK3+S8), and GNDS (GK1+NK3+D1+S8)] by mixing lactic acid bacteria and yeast, and S6 was sprayed. The microbial composition of fermented sausage was analyzed [aerobic bacteria (AC), Lactobacillus spp. (LABC), Staphylococcus spp. (STPC), and yeast and mold (YMC)], and pH and electronic nose and tongue measurements were taken. The AC, LABC, STPC, and YMC values of the control and treatment groups tended to increase during fermentation (p>0.05). The STPC values of the GD, GS, ND, and GDS groups were similar to that of the control on day 3. The pH of the control on day 3 was significantly lower than that of the GD, ND, and GND groups (p<0.05). Higher levels of 4-methylpentanol, 2-furanmethanol, and propyl nonanoate, which provide a "fermented" flavor, were detected in the GD group compared to in the control and other treatment groups. GD and ND groups showed higher umami values than the control and other treatment groups. Therefore, it is expected that GD can be valuable as a starter culture unique to Korea when manufacturing fermented sausage.

• 한국축산식품학회지
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• 제41권2호
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• pp.196-213
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• 2021

The objective of this study was to determine the effects of yeast cultures (Candida zeylanoides and Debaryomyces hansenii) isolated from traditionally dry fermented Turkish sucuks, on some physicochemical and microbiological properties of the product. Eight different batches of the sucuks were produced by the inoculation of yeast and lactic acid bacteria (LAB) cultures (Lactobacillus curvatus, Lactobacillus plantarum and Lactobacillus sakei) in different combinations. The sucuks were ripened for 12 days and analyzed at 1st, 6th, and 12th days of ripening. Percent moisture content, pH, water activity (aw) and residual nitrite values of the sucuk inoculated with the yeast cultures were higher at the end of the ripening. The use of yeast cultures decreased hardness, gumminess, and chewiness values of the sucuk while increased adhesiveness values. Major volatile groups were aldehydes, terpenes, and sulphur compounds in the sucuk samples. The most noticeable results were for sensory properties of the sucuk that were positively improved by the yeast cultures.

• 한국축산식품학회지
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• 제43권5호
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• pp.877-888
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• 2023

We studied the proteolysis and conducted a sensory evaluation of fermented sausages using strains derived from Kimchi [Pediococcus pentosaceus-SMFM2021-GK1 (GK1); P. pentosaceus-SMFM2021-NK3 (NK3)], Doenjang [Debaryomyces hansenii-SMFM2021-D1 (D1)], and spontaneous fermented sausage [Penicillium nalgiovense-SMFM2021-S6 (S6)]. Fermented sausages were classified as commercial starter culture (CST), mixed with GK1, D1, and S6 (GKDS), and mixed with NK3, D1, and S6 (NKDS). The protein content and pH of GKDS and NKDS were significantly higher than those of CST on days 3 and 31, respectively (p<0.05). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the NKDS had higher molecular weight proteins than the GKDS and CST. The myofibrillar protein solubility of the GKDS and NKDS was significantly higher than that of the CST on day 31 (p<0.05). The GKDS displayed significantly higher pepsin and trypsin digestion than the NKDS on day 31 (p<0.05). The hardness, chewiness, gumminess, and cohesiveness of the GKDS were not significantly different from those of the CST. The GKDS exhibited the highest values for flavor, tenderness, texture, and overall acceptability. According to this study, sausages fermented using lactic acid bacteria (GK1), yeast (D1), and mold (S6) derived from Korean fermented foods displayed high proteolysis and excellent sensory evaluation results.

• 한국식품저장유통학회지
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• 제30권6호
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• pp.1056-1071
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• 2023

본 연구에서는 B. velezensis NY12-2, D. hansenii D5-P5, 그리고 E. faecium N78-11 등을 단일 또는 복합 종균으로 구성하여 막장을 옥외와 발효실(35℃) 등의 발효 장소를 달리하여 90일간 발효장소와 종균이 품질변화에 미치는 영향을 살펴보고자 수행하였다. 먼저 발효환경 및 종균처리와 무관하게 수분함량과 pH는 발효기간이 경과함에 따라 전반적으로 감소하는 경향을 보였으며, 그로 인해 염도와 산도는 증가하였다. 또한, 총균수는 발효기간이 경과함에 따라 유의적으로 증가한 반면, 유산균 수는 감소하였고, 곰팡이 수는 발효기간 내내 비슷한 수준을 유지하였다. 환원당 함량은 초기에 5.33±0.02-5.72±0.15%에서 발효 30일 차에 가장 높게 증가하였다가 90일 차에는 미생물의 영양원 소비, Maillard 반응, 알코올 및 유기산 발효에 따른 당 소비로 인해 옥외와 발효실에서 각각 7.28±0.14-8.43±0.05%와 6.02±0.00-7.39±0.11%로 급격히 감소하였다. 제조 직후 막장 시료들의 아미노산 질소 함량은 122.75±0.99-155.01±2.98 mg%이었고, 발효 30일 만에 대부분의 시험구(대조구 제외)들은 500 mg% 이상 상승하였으며, 특히 발효실에서 35℃, 90일간 발효한 복합시험구(M)는 최대 668.43±0.99 mg%로 가장 높은 값을 보였다. 총아미노산 함량은 제조 직후 1,166.89-1,527.12 mg/g 이었고, 90일 발효 후 옥외(3,150.73-3,615.08 mg/g) 대비 발효실에서 3,661.71-4,644.04 mg/g 수준으로 높은 값을 나타내었다. 특히 단일시험구(S3)와 복합시험구(M)는 옥외에서 각각 3615.08 mg/g과 3546.91 mg/g을, 발효실에서는 4484.95 mg/g과 4644.04 mg/g으로 시험구 중 높은 값을 나타내었다. 또한, 발효 후 막장 시료들 간 세균군집의 풍부도는 발효실이 옥외에 비해 상대적으로 높았고 B. subtilis, W. coagulans, E. faecium 등이 높은 빈도로 검출되었지만, 종 다양성 및 균등성에서는 두 환경 간 큰 차이는 없었다. 반면, 진균군집의 경우, 발효실에서의 풍부도가 옥외에 비해 상대적으로 낮았는데, 종 다양성 및 균등성 또한 옥외 대비 상대적으로 낮은 값을 보였다. 주로 검출된 진균들은 A. tubingensis, A. niger, D. hansenii, Z. rouxii 등이었다. 또한, 전자혀를 이용한 막장의 맛 패턴 분석결과에서도 발효실에서 복합종균을 접종하여 제조한 시험구(M)에서 낮은 짠맛과 높은 감칠맛 강도를 나타내었는데, 이는 아미노산 질소와 아미노산 등 함량이 높았던 품질 특성과 깊은 상관성을 보여주었다. 종합적으로, 본 연구에서 옥외와 발효실이라는 발효환경 조건과 복합종균 사용이 미생물 군집 형성에 영향을 주어 맛 성분 증가라는 긍정적인 효과와 연계됨을 알 수 있었다. 향후 유용 종균과 함께 일정한 온도의 발효환경을 조성하여 제조한다면 장류식품의 품질향상 및 발효관리에 도움을 줄 수 있을 것으로 기대된다.

• Journal of Microbiology and Biotechnology
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• 제26권9호
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• pp.1533-1541
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• 2016

Samples of doenjang (a fermented soybean paste) were prepared with different types of salts; purified salt (PS), 3-year-aged solar salt (SS3), 1-year-aged solar salt (SS1), and bamboo salt (BS, 3^rd processing product). For starter doenjang samples, selected starters comprising two bacilli, one yeast, and one fungus were inoculated, whereas for non-starter doenjang samples, microorganisms present in rice straw were inoculated after enrichment. The doenjang samples were fermented for 13 weeks at 25℃. During the fermentation period, SS and BS doenjang samples showed higher bacilli counts as well as much lower yeast counts than PS doenjang. At 13 weeks, yeast counts of starter doenjang samples were 7.75, 5.69, 6.08, and 4.74 log CFU/g for PS, SS3, SS1, and BS doenjang, respectively. For non-starter doenjang samples, counts were 7.17, 5.05, 5.92, and 4.54 log CFU/g for PS, SS3, SS1, and BS doenjang, respectively. SS and BS promoted growth of bacilli but inhibited growth of yeasts compared with PS. Debaryomyces hansenii was the dominant yeast in PS doenjang, whereas Candida guilliermondii and Pichia sorbitophila were dominant in SS and BS doenjang. In the sensory evaluation, SS and BS doenjang scored better than PS doenjang. In conclusion, SS and BS seem better than PS for production of high-quality doenjang.

• Journal of Microbiology and Biotechnology
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• 제19권8호
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• pp.743-748
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• 2009

Fungal diversity during composting was investigated by culture-independent rDNA sequence analysis. Composting was carried out with pig manure and mushroom cultural waste using a field-scale composter (Hazaka system), and samples were collected at various stages. Based on partial sequence analysis of large subunit (LSU) ribosomal RNA (rRNA) and sequence identity values, a total of 12 different fungal species were found at six sampling sites; Geotrichum sp., Debaryomyces hansenii, Monographella nivalis, Acremonium strictum, Acremonium alternatum, Cladosporium sphaerospermum, Myriangium durosai, Pleurotus eryngii, Malassezia globosa, Malassezia restricta, Rhodotorula glutinis, and Fusarium sporotrichioides. Geotrichum sp. of the class Saccharomycetes was the most predominant fungal species throughout the composting process (185 out of a total of 236 identified clones, or 78.4%), followed by Acremonium strictum (7.6%), Monographella nivalis (5.1%), and Pleurotus eryngii (3.8%). The prevalence of Geotrichum sp. was the lowest (61.1%) at the beginning of composting, and then gradually increased to 92.5% after 10 days of composting.

• Journal of Microbiology and Biotechnology
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• 제24권8호
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• pp.1088-1095
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• 2014

A systematic investigation was performed on the bacterial, Bacillus, fungal, and yeast communities of the three types of Daqu (mechanically prepared, manually prepared, and mixed prepared) used in Baiyunbian Company by reconditioning PCR-denaturing gradient gel electrophoresis (PCR-DGGE). The DGGE results showed that the microbes in the three types of Daqu were mainly thermotolerant and thermophilic microbes, and the most dominant bacterial species were Bacillus and Virgibacillus, followed by Lactobacillus and Trichococcus. Furthermore, the dominant fungi were found to be molds, such as Rasamsonia, Penicillium, Aspergillus, and Monascus, and the dominant yeasts were Saccharomyces cerevisiae, Saccharomycopsis fibuligera, Pichia anomala, and Debaryomyces hansenii. In general, the three types of Daqu showed slight differences in microbial communities, and the Shannon indexes (H') of the manually prepared and mechanically prepared Daqu were similar. The results suggest that mechanically prepared Daqu can replace manually prepared Daqu in liquor production, and this research provides useful information for liquor production and process improvement.