• Asian-Australasian Journal of Animal Sciences
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• v.31 no.4
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• pp.585-594
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• 2018

Objective: This study was to determine the bacterial diversity and monitor the community dynamic changes during storage of vacuum-packaged sliced raw beef as affected by Lactobacillus sakei and Lactobacillus curvatus. Methods: L. sakei and L. curvatus were separately incubated in vacuumed-packaged raw beef as bio-protective cultures to inhibit the naturally contaminating microbial load. Dynamic changes of the microbial diversity of inoculated or non-inoculated (control) samples were monitored at $4^{\circ}C$ for 0 to 38 days, using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Results: The DGGE profiles of DNA directly extracted from non-inoculated control samples highlighted the order of appearance of spoilage bacteria during storage, showing that Enterbacteriaceae and Pseudomonas fragi emerged early, then Brochothrix thermosphacta shared the dominant position, and finally, Pseudomonas putida showed up became predominant. Compared with control, the inoculation of either L. sakei or L. curvatus significantly lowered the complexity of microbial diversity and inhibited the growth of spoilage bacteria (p<0.05). Interestingly, we also found that the dominant position of L. curvatus was replaced by indigenous L. sakei after 13 d for L. curvatus-inoculated samples. Plate counts on selective agars further showed that inoculation with L. sakei or L. curvatus obviously reduced the viable counts of Enterbacteraceae, Pseudomonas spp. and B. thermosphacta during later storage (p<0.05), with L. sakei exerting greater inhibitory effect. Inoculation with both bio-protective cultures also significantly decreased the total volatile basic nitrogen values of stored samples (p<0.05). Conclusion: Taken together, the results proved the benefits of inoculation with lactic acid bacteria especially L. sakei as a potential way to inhibit growth of spoilage-related bacteria and improve the shelf life of vacuum-packaged raw beef.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.788-793
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• 1999

In this study, it was investigated that the isolation and identification of spoilage bacteria from contaminated aseptic packaged cooked rice, the potential for application of acidic electrolyzed saline solution (AESS) as water-for-cooked rice and the microbiological safety of AESS-based cooked rice. Five strains of Bacillus subtilis and a B. cereus strain among the total six isolates were partially identified by biochemical method and by Microbial Identification System (MIS). The bactericidal effect of AESS was similar as 0.1% NaOCl and 70% ethanol solution, or better than that. All of the test microorganisms except Bacillus spp. that were exposed to AESS for five seconds were destructed. The effect of AESS against Bacillus spp. was much better than that of the two solutions and all of them were destructed or inhibited on exposure for five minutes. The pH value of cooked rice prepared using AESS was in the range of 3.6 to 4.3 and was not almost changed through the storage period. Various concentrations of cell suspension of Bacillus isolates were inoculated to cooked rice, which were prepared with tap water and AESS, and stored at $37^{\circ}C$ for two weeks. The result was shown that the bacteria in tap water-based cooked rice appeared normal cell growth, while they were completely repressed in AESS-based cooked rice.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.205-211
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• 1991

Ethanol extracts of amur cork, elm root, plantain and dandelion which are edible and can be mass produced at farm were examined their inhibitory activity against food spoilage microorganisms at their concentrations and the extracts were fractionated by some solvents with checking effective fractionate. Above $500{\sim}2000\;ppm$ of the extracts inhibited completely the test microorganisms with a few exception. One thousand ppm of amur cork exract inhibited B. cereus completely. L. mesenteroides by 500 ppm of amur cork and 2000 ppm of elm root and plantain showed a pretty good inhibition. The extracts which showed good inhibition to the test microorganisms were fractionated with chroloform, ethylacetate, butanol and water in order and the fractionates of butanol and chroloform showed comparetively higher inhibition than others generally. Inhibition rate of each fractionate were as follows ; B. cereus was inhibited completely at 500 ppm of chroloform fraction, and 1000 ppm of ethyl acetate and butanol and L. mesenteroides was 500 ppm of butanol fraction. P. fluorescens was inhibited partly by 500 ppm of butanol and ethyl acetate fraction.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.269-277
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• 2009

This paper reports the results of the research on the effects of probiotic yogurt on the microbiological quality, pH, and sensorial characteristics of fresh chicken meat when packed with probiotic yogurt. The chicken meat pieces were packed with yogurt and were stored at $10^{\circ}C$ for 7 days. Samples were taken after 0, 2, 4, and 7 days of storage, and were analyzed for total bacterial count, E. coli, and coliform, and for the chemical parameters, including the pH. In the control group (packed without yogurt), the Pseudomonas species predominated when the spoilage was obvious after 4-day storage at $10^{\circ}C$. The yogurt-mixed chicken meat package was found to have a significantly lower total viable count and significantly fewer coliform bacteria during storage. Furthermore, the yogurt package showed a growth-inhibiting effect on the Salmonella typhimurium, which were inoculated into the chicken meat pieces for the study. The study findings indicate that probiotic yogurt can be used in packing fresh chicken meat to decrease the population of spoilage bacteria therein and to extend its shelf life.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.849-853
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• 2000

This study was examined for antibacterial effect of various molecular weight of chitosan against spoilage bacteria in emulsion sausage. Four different kinds of chitosan, molecular weights (M.W.) of 1 kDa, 5 kDa, 30 kDa and 120 kDa, wee used. The more molecular weight of chitosan is high, the more storage property of sausage is good during storage at $30^{\circ}C$. Storage properties of sausages between added 0.5% of M.W. 120 kDa chitosan and 150 ppm of sodium nitrite were about the same. Effect of growth-inhibitory of spoilage bacteria was not detected 0.2% of M.W. 1kDa chitosan 0.2% of M.W. 5kDa chitosan have growth-inhibitory effect over 80% against only 3 strains among bacteria isolated from spoiled emulsion sausage. But, 0.2% of M.W. 30 kDa chitosan have growth-inhibitory effect of 80% against all strains of bacteria related to spoilage of emulsion sausage, except S. typhimurium, Especially, 0.2% of M.W. 120 kDa chitosan inhibited over 80% growth against all strains used in this study. The antibacterial activity was increased with their molecular weight.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.7
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• pp.996-1006
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• 2019

Objective: This study aimed to gain deeper insights into the dynamic changes in spoilage fungi populations during fermentation and the influence of traditional additives on silage quality. Methods: Elephant grass (Pennisetum purpureum) was prepared without any additive (control), and with the addition of 0.5% salt, and 0.5% salt-0.2% sugar mixture. The fungal community was then determined using a classic culturing method and high-throughput sequencing at 0, 5, 15, and 60 days after ensiling. Results: The results showed that the fungal community of elephant grass silage varied significantly between the natural fermentation without any additive and the two additive groups. The diversity and relative abundance of spoilage molds in the control group were much higher than those in the two treatment groups (p<0.05). Three species of yeasts (Candida sp., Pichia sp., Trichosporon sp.) and four spoilage molds (Fusarium sp., Aspergillus sp., Muco sp. and Penicillin sp.) were the predominant fungi in elephant grass during natural fermentation from 0 to 60 days, which were found to be significantly decreased in salt and sugar additive groups (p<0.05). Meanwhile, the diversity and relative abundance of undesirable molds in the 0.5%-salt additive group were the lowest among all groups. Conclusion: Adding salt and sugar, particularly 0.5% salt, is a promising effective approach to reduce the amount of undesirable fungi thus, improving the silage quality of elephant grass in northern Vietnam.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.558-561
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• 2000

Strain JW3 was isolated from commercial Swiss cheese products and identified as a bacteriocin producer. Lactococcus lactis JW3 showed a broad spectrum of activity against most of the non-pathogenic and pathogenic microorganisms tested by the modified deferred method. Lacticin JW3 also showed a relatively broad spectrum of activity against non-pathogenic and pathogenic microorganisms as assessed using the spot-on-lawn method. It demonstrated a typical bactericidal mode of inhibition against Leuconostoc mesenteroides KCCM 11324.

• Korean Journal of Microbiology
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• v.4 no.2
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• pp.11-14
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• 1966

The deterioration of cellulosic materials due to the growth of mildew causes enormous loss to us. It is, therefore, necessary to give adequate protectional treatment against mildew spoilage on cellulosic materials. In this study, fourteen chemicals were treated to the strain of Chaetomium globosum A.T.C.C., then phenyl mercuric acetate (P.M.A) was proved to be a most effective fungicide out of various chemicals. Another chemicals, such as Na-pentachlorophenolate, tuget, $\alpha$-naphthol, caprylic acid and orthocidc were also proved to be effective mildew-proofing agents.

• Journal of the Korean Professional Engineers Association
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• v.16 no.1
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• pp.71-77
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• 1983

Meat itself contains all the essential nutrients for the organisms, because it is high in moisture, rich in nitrogenous, Plentifully supplied with minerals and accessory growth factors, usually has come fermantable carbohydrates and is at a faverable PH for most microorganisms. So, microorganisn can grow and multiply rapidly well in it and caused spoilage of meat and their Product. Therefore, storage and handling of meat must be Strictly controlled on contamination and growth of organism by a low temperature, among the low temperature control, chilling control of meat is one of the best method as good retention for meat quality.

• Journal of Ginseng Research
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• v.18 no.1
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• pp.49-52
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• 1994

A yeast was isolated from the spoiled ginseng product. The isolate was ellipsoidal shaped yeast measured around 2.0 to 2.5 w in diameter. The strain formed pseudomycelium on potato-dextrose agar medium. The isolated yeast used glucose as fermentable sugar, and showed assimilation activity for glucose, sorbitol and mannitol. The strain was also able to grow in the presence of 1% acetic acid and 50% (w/v) glucose-yeast extract agar. The isolated osmophilic yeast was identified as a strain of Zygosauharomyce sp.