• Food Industry
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• s.19
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• pp.20-24
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• 1974

• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.1-5
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• 1986

Putrefactive microorganisms from infected onion bulbs collected at several areas were isolated and identified. The infecting microorganisms were mostly the species of Botrytis, Fusarium, Penicillium, Ericinia and Pseudomonas, among which the last was not pathogenic to onion bulbs. Fumigation of onion bulbs with Tetrachloroisophthalonitrile cut down decay rate by half of the control and the onion bulbs stored at 80% RH showed slow decay rate than those stored at 90% RH. The decay of onion bulbs was mainly caused by molds and the portions of them were 78-85% of Botrytis, 11-17% of Fusarium and 3-5% of Penicillium.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1011-1020
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• 2001

Volatile organic components from onions stored in the different decay conditions were extracted by SDE apparatus and analyzed by GC-FID and GC/MS. Components of 115, 143, 123 and 137 were identified in fresh onions, decayed onions without heating, half-decayed and complete-decayed onions after heating, respectively. These components included esters, aldehydes, ketones, alcohols and sulfur-containing compounds. Dimethyl trisulfide, dimethyl disulfide, dipropyl trisulfide and 3,5-diethyl-1,2,4-trithiolane were the main sulfur-containing components in fresh onions and decayed onions without heating. As spoilage of onions, the concentrations of sulfur-containing components of volatile extracts significantly decreased. Apart from sulfur-containing components, volatile organic components in half-decayed and complete-decayed onions after heating were mainly composed of esters, aldehydes, ketones and alcohols. Ketones of volatiles in complete-decayed onions after heating were high relatively.

• Food Industry
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• s.8
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• pp.10-15
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• 1972

• Korean Journal of Food Science and Technology
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• v.24 no.1
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• pp.29-30
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• 1992

Three microorganisms were isolated from staled market soybean curd and confirmed their reproducibility of putrefaction. The isolates were identified as Acinetobacter calcoaceticus var. anitrat(97.9%) and Klebsiella pneumoniae subgroup pneumoniae(99.0%). The third microorganism has same characteristics as A. calcoaceticus var. anitrat except mucoid production.

• Food Industry And Nutrition
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• v.10 no.1
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• pp.11-16
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• 2005

식물성 단백질의 주요 공급원이며 우리나라 전통식품 중의 하나인 두부의 유통기한을 정량적으로 예측할 수 있는 수학적 모델을 개발하고자 온도와 초기균수에 따른 두부 부패세균의 성장 실험 결과를 데이터베이스화하여 이를 바탕으로 균의 성장을 정량적으로 평가할 수 있는 수학적 모델을 개발하였다. 근의 증식 지표인 최대증식속도상수(k), 유도기(LT), 세대시간(GT)은 온도에 지배적인 영향을 받았으며, 초기균수에 따른 유의 적 인 차이 는 없었다(p<0.05). 최대증식속도상수와 온도 및 초기균수의 상관관계를 나타내는 수학적 정량평가모델인 square root model을 이 용하여 두부 부패 세균의 성장을 정량적으로 예측할 수 있는 모델$({\surd}{\kappa}=0.016861(T+6.87095))$을 개발하였으며 실험치와 예측치의 상관계수는0.969이었다. 이 예측 정량평가모델로부터 예측한 최대증식속도상수와 두부의 관능적 부패시 점을 반영 한 Gompertz 변형 모델을 이용하여 두부의 유통기한을 예측할 수 있는 모델$(Spoilage-critrion(hr)=\frac{2{\times}Ln2+Ln[(Nmax/No)-1])}{k}$을 개발하였다

• Food Engineering Progress
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• v.13 no.2
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• pp.117-121
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• 2009

Detection of spoilage odors from beef during storage was investigated using sensory evaluation with R-index, and microbial assay for Pseudomonas. Beef samples were tested to measure the flavor changes, which were converted to R-index, and the Pseudomonas levels during storage. There was a steep rise in R-index until 36 hr after storage at 25$^{\circ}C$, and then a gentle rise from 48 hr, whereas, there was a steady rise in R-index in the whole range of storage at 5$^{\circ}C$. Detection time of spoilage odors according to R-index was statistically analyzed at $\alpha$=5% to be at 30.92${\pm}$3.47 hr and 169.80${\pm}$11.27 hr for 25 and 5$^{\circ}C$ storage, respectively, and analyzed at $\alpha$=1% to be 34.80${\pm}$4.01 and 176.41${\pm}$9.89 hr for 25 and 5$^{\circ}C$ storage, respectively. At the detection times of spoilage odors, the Pseudomonas levels were found to be almost the same, but less than 6-7 log CFU/g generally known as a standard level at occurrence of spoilage odors in beef. This indicated that some other factors than the Pseudomonas reactions could be associated with generation of spoilage odors.

• Korean journal of food and cookery science
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• v.4 no.1
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• pp.41-46
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• 1988

Omija tea with a pH range of 2.8~3.0 was stored at $25^{\circ}C$ to study its spoilage due to microbial growth. Titratable acidity was increasing during the storage period in the tea stored with the Omija fruits but not in removed of the fruits after extraction. Microbial cells began to show up earlier in the tea without the fruits than that with the fruits. Four strains of yeasts and a strain of mold were isolated from spoiled Omija tea. Morphological, cultural and physiological characteristics of yeasts were investigated and the yeasts were identified as Rhodotorula rubra, Saccharomyces kluyveri, Cryptococcus hungaricus and Candida humicola. Morphological characteristics of the isolated mold was observed and the mold was identified as Mucor circinelloides f. janssenii.

• Korean Journal of Food Science and Technology
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• v.19 no.5
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• pp.453-455
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• 1987

Swollen commercially canned grapes and peaches were collected to investigate the microorganisms involved in their spoilage. 6 of 52 grape and 19 of 23 peach samples were found to be spoiled by microorganisms. Yeasts were the only spoilage microorganisms of canned grapes with Saccharomyces cerevisiae as the leading spoilage yeast. Yeasts and bacteria were found from spoiled canned peaches. S. cerevisiae and Torulopsis stellata were the most important spoilage yeasts of canned peaches. Lactic acid bacteria, belonging to genera of Lactobacillus and Leuconostoc, were the most frequently found spoilage bacteria. Only one spore-forming bacterium, Bacillus licheniformis, was involved in the spoilage of canned peaches.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.109-114
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• 2006

Yam has been recognized as healthy food due to its various biological activities, such as anti-obesity, antimicrobial, anticancer and immuno-stimulation activities, and its consumption has been increased during last decades. In this study, to investigate low-temperature, long-term storage of yam and to develop processed yam products, yam-putrefactive psychrotrophic bacteria were isolated from rotted yam and identified based on BBL identification system, fatty acid analysis in cell membrane and 16S rDNA sequence analysis. The putrefaction activity of isolated thirteen bacteria was evaluated using yam-slices (NaOCl-treated, autoclaved yam and without treatment), and YAM-10 and YAM-12 were identified as major psychrotrophic putrefactive bacteria. Both YAM-10 (Pseudomonas cepacia) and YAM-12 (Pseudomonas rhodesiae) bacteria grew well at 4$\sim$12$^{\circ}C$ and showed strong activity of polymer degrading enzymes, especially amylase, carboxy methyl cellulase and xylanase, at 20$^{\circ}C$. But they failed to grow at acidic pH (<5) or alkaline pH (>10). Our results suggested that the control of psychrotrophic Pseudomonas sp. by pH change and inhibition of polymer degrading enzymes, such as amy-lase, are necessary to long-term storage of yam.