• Food Science and Biotechnology
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• v.15 no.3
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• pp.469-473
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• 2006

Film-forming yeasts generate an undesirable yeasty flavor in fermented vegetables such as kimchi in the presence of oxygen. Antimicrobial materials including garlic oil (GO), heated garlic (HG), and allyl alcohol (AA) were investigated for use as alternative natural food preservatives to inhibit the growth of film-forming yeasts in fermented vegetables. Using the fermentation of cucumber pickles as a model system, GO, HG, and AA were effective in preventing film formation at concentrations of 0.006, 3.0, and 0.02%, respectively. The effectiveness of HG in preventing the growth of a film yeast, Hansenula anomala, was not influenced by pH, while that of potassium sorbate, a typical anti-yeast food preservative, was highly dependent on pH. All tested materials were effective when added at the beginning of fermentation due to their negligible inhibitory activity toward lactic acid bacteria.

• Microbiology and Biotechnology Letters
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• v.6 no.2
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• pp.81-84
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• 1978

Film-forming yeasts were isolated from deteriolated soybean paste and after identification factors affected on the growth of the organisms were studied to provide information on the protection of the product from deteriolation. The isolated yeasts were identified as Pichia membranaefaciens. The yeasts could grow within the temperature limit of 10$^{\circ}C$ and 68$^{\circ}C$ with optimum at 25$^{\circ}C$. The optimum pH was 6.0 and the growth was reduced in order at 7.0, 5.0, 8.0 and 4.0. The maximum concentration of sodium chloride in Hayduck solution was 15％ above which the yeasts ceased to grow.

• Korean Journal of Food Science and Technology
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• v.7 no.2
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• pp.61-68
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• 1975

This study was conducted (1) to isolate the film-forming yeast from the commercially available soy sauce, (2) to identify the state of soy sauce fermentation by the use of yeasts, (3) to confirm characteristics of yeasts. The result were as follows. 1. These yeast strains in the soy sauce fermentation test showed full fermentation of whole sugar content, reduction of the pure extract and relative reduction in total nitrogen. Soy sauce color was somehow faded to lower the stability of soy sauce. 2. In anti-fungal activity test butylparaben at a higher level 60 ppm., sodium propionate 2,400 ppm, sodium benzoate 800 ppm., menadion 165 ppm, showed their anti-fungal effect, while alcohol did not show the effect in the 3% additive group. 3. The optimum sodium chloride concentration for these strains in the 2% G.Y.P. medium was 5% and optimum temperature was $30^{\circ}C$. The extinction temperature was $62^{\circ}C$ for strain No-1 and No-3, and was $65^{\circ}C$ for No-2 and No-4. 4. The film-forming soy sauce turned out in the gas chromatogram to possess much flavor of low boiling point as compared with the standard. These flavors were considered due to flavor spoilage of the soy sauce. 5. These isolated yeasts were identified Saccharomyces rouxii (film-forming yeast) in the Lodder's taxanomic study.

• Korean Journal of Microbiology
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• v.49 no.3
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• pp.286-291
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• 2013

Soybean pastes with 8% (w/w) salinity were prepared instead of soybean paste with 14% (w/w) salinity to meet the growing demands of Korean's low sodium diet. After aging, white films had appeared on the surface of all low-salted soybean pastes [8% (w/w) salinity] unlike high-salted soybean pastes [14% (w/w) salinity]. All of eight microbes isolated from the surface film were identified as Pichia kudriavzevii. Eleven Bacillus strains with good characteristics of fermentation were isolated from traditionally fermented soybean pastes in order to preserve their unique flavors and aromas after aging, and as a result of analyzing the biochemical characteristics and 16S rRNA sequences, those were identified as B. subtilis, B. licheniformis, and B. methylotrophicus. All of the Bacillus isolates had antagonistic activities against 8 isolates of the film-forming yeasts and harbored the genes for synthesis of antimicrobial surfactants including lichenysin and/or surfactin.

• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.159-163
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• 1983

Film-formation, which often occurs during storage of apple wine, owing to contamination by film-forming yeasts, results in inferior products. Therefore, for the purpose of preventing this occurrence, we isolated and identified yeast strain. Among the total number of 45 yeast strains which were isolated from contaminated apple wine in winery, the strains FY-4 and FY-5 were found to be useful. The strain FY-5, which greatly formed film on apple wine, was identified as Hansenula beijerinckii or similar strain according to taxonomic characteristics.

• KSBB Journal
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• v.18 no.2
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• pp.117-121
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• 2003

The study was carried out to determine the effect of storage property and qualities on soybean sauce and paste by adding different amount of pyroligneous liquor obtained by sujpercritical fluid extraction(SFE). Purified pyroligneous liquor obtained by SFE at 4$0^{\circ}C$/110 bar contained p-cresol, o-cresol and m-cresol food sterilizers, but no toxic substances such as tar, scorched, furfuraland and monophenol. Thus pyroligneous liquor was considered to be suitable as natural food preservative. In case of soybean sauce, pyroligneous liquor was tested to determine the potential of natual food preservative to prevent flim formation on soybean ksauce 15days at 3$0^{\circ}C$. Increasing amounts of purified pyroligneous liquor added to soybean sauce prevented film forming yeasts. In case of paste, pyroligneous liquor was tested to determine the potential of natural food preservative to inhibit browning on paste 60 days at 3$0^{\circ}C$. Purified pyroligneous liquor added to paste inhibited brown pigment. As a result, purified pyroligneous liquor offered a promising way of improving the quality and storage property of soybean sauce and paste.

• Microbiology and Biotechnology Letters
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• v.2 no.1
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• pp.9-11
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• 1974

This experiment was carried out to conform the antseptic effect of Astradix-P, as a yeaststatic substance on the growth of film forming yeasts, which were isolated from denatured home prepared Korean soy sauce. It resulted that Astradix-P did not give any antiseptic effect, if these yeasts were inoculated into soy sauce medium, but in the ordinary medium the yeast growth were strongly inhibited. Consquently the possiblities of the practical application of the Astradix-P into the home-preserving soy sauce was primarily remained in doubt at this moment. This result might be caused from the reason that the basic amino acids, originally existed in soy sauce, eg, arginine, histidine and lysine etc., had anticipated with the antagonistic action and thereby they made the Astradix-P inactive to these yeast, which already they have been recognized in the previous works.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.3
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• pp.327-334
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• 2017

Water and 75% ethanol extracts were prepared from defatted green tea seeds and evaluated for their anti-yeast activities. The antimicrobial activities of defatted green tea seed extracts (DGTSEs) were tested against food-spoilage bacteria, yeasts, and molds. DGTSEs exhibited antimicrobial activities with minimum inhibitory concentrations of $39{\sim}1,250{\mu}g/mL$ against three bacteria, two molds, and all tested yeast strains. Ethanol extract showed higher antimicrobial activity than water extract. The stability of anti-yeast activities of DGTSEs was examined under different conditions of temperature, pH, and NaCl concentrations. The anti-yeast activities of DGTSEs were stable at pH 3~9, 0~20% NaCl, and $100^{\circ}C$ for 30 min. However, anti-yeast activities of DGTSEs decreased upon heating at $70^{\circ}C$ for 24 h or $121^{\circ}C$ for 15 min. DGTSEs were applied to food models to determine their inhibitory effects on yeast film formation. Water and 75% ethanol extracts were effective in preventing yeast film formation at concentrations more than 156 and $39{\mu}g/mL$ in soy sauce, 156 and $78{\mu}g/mL$ in pickle sauce, and 78 and $39{\mu}g/mL$ in kimchi, respectively.