• Journal of Dairy Science and Biotechnology
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• 제22권1호
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• pp.27-35
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• 2004

The shelf lift of market milk should be determined based on the flavor which is influenced by environmental and sanitary conditions of dairy farm, milk processing plant, and storage and transportation facility as well as compositional quality, such as protein and fat, of the milk itself. The legal shelf life of market milk is often limited by microbiological quality, e.g. total bacterial count, coliform count, and food poisoning bacteria. The bacteria involved with milk spoilage and poisoning are originated from bacteria contaminating milk after pasteurization or spores surviving the heat treatment of pasteurization. The important factors which influence the shelf life of market milk are microbiological quality of raw milk, pasteurization condition, post-pasteurization contamination, and temperature during storage and transportation. The organoleptic quality and shelf life of market milk should be further improved by satisfying the consumer's taste, which depends on somatic cell count and bacterial count of milk, feed quality, foreign substance in milk, and physical treatment during processing and transportation.

• Food Science and Biotechnology
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• 제18권2호
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• pp.425-431
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• 2009

Antimicrobial coating on chicken carcasses may reduce the effects of cross-contamination and improve product shelf-life and safety. Thyme oil was mixed at 0.5%(v/v) with a pre-gelatinized pea starch coating solution. The coating solution was spread on chicken breast meat after inoculation with selected spoilage and pathogenic bacteria. After inoculation, the chicken meats were packaged in plastic bags and stored at $4^{\circ}C$. During 12 day storage, total aerobic bacteria, lactic acid bacteria, and inoculated organisms were counted at 4 day intervals. Thyme oil treatments reduced the viability of Salmonella as well as the growth of Listeria and Pseudomonas by 2 log CFU/g, and appeared to eliminate inoculated Campylobacter during storage. The addition of thyme oil increased the viscosity of the pre-gelatinized pea starch solution. The results suggested that thyme oil inclusion in an edible starch coating may be a satisfactory delivery system to enhance the safety of processed fresh meat.

• 한국식품조리과학회지
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• 제12권3호
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• pp.312-319
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• 1996

굴(Crassostrea virginica)과 Weakfish(Cynoscion regalix)를 냉장(6$^{\circ}C$), 빙장($0^{\circ}C$), 부분동결저장(-4$^{\circ}C$) 및 동결저장(-2$0^{\circ}C$)온도에서 45일간 저장하면서 생균수 와 microflora의 변화를 조사하였다. 각 온도에서 저온저장중 굴로부터 255주, Weakfish로부터 240주, 합계 495주를 분리하여 microflora의 변화를 조사하였다. 저장직전의 생선에서 생균수는 굴이 4.9$\times$10/ sup 5/CFU/g, Weakfish가 $1.5\times$$10^4$CFU/$cm^2$였다. 저장직전의 굴에서는 Pseudomonas ll1III/IV가 67%, Vibrio가 20%를 차지하였다. Weakfish에서는 Acinetobacter가 40% Moraxella가 33%로서 주종을 이루었으며 Pseudomonas와 Vibrio는 아주 적은 비율을 차지하였다. 굴의 저온저장중 microflora는 저장온도에 큰 관계 없이 모든 저장온도에서 Pseudomonas lIII/IV-H가 전체 균주의 67.4%, Flavobacterium/Cytophaga가 9.3%, 다음으로는 Vibrio가 6.3%를 차지하였고 약 15%의 세균은 동정하지 못하였다. Weakfish의 저온저장중 microflora는 냉장, 빙장, 부분동결저장한 경우에 비호염성균인 Pseudomonas III/IV-NH가 전체 균주의 60~100%를 차지하였으며 동결저장한 Weakfish에서는 Moraxella가 전체 분리 균주의 40~60%를 차지하였다. 전체적으로 굴에서는 호염성 균주(pseudomonas III/ IV-H와 Vibrio)가 우세하였고 구균류가 분리되지 않았으나 Weakfish에서는 비호염균주(PseudomonasIII/IV -NH와 Moraxella가 우세하였으며 구균류가 4.6% 검출되었다. 저온저장한 굴과 Weakfish에서 Vibrio의 검출률은 굴에서 Weakfish보다 3배 높았으며 Listeria spp. 는 검출되지 않았으나 강한 용혈작용을 가진 균들이 각각 9주, 8주씩 분리되어 주의가 요망된다.

• 한국식품저장유통학회지
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• 제6권2호
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• pp.245-254
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• 1999

Lactic aicd bacteria(LAB)는 전통적으로 식품의 발효과정 중에 사용되는 미생물이다. Lactic acid bacteria를 이용한 bacteriocinogenic culture와 lactic acid bacteria에서 생산되는 산물은 식품의 부패에 원인이 되는 미생물과 병원성균에 대한 생육억제효과을 지니고 있다. 이러한 이유로 생선제품, 유제품. 육제품과 발효되지 않은 냉장식품 등의 식품저장에 lactic acid bacteria를 이용한 연구가 다양하게 수행되어져 오고 있었으나 과실 및 채소류에서의 lactic acid bacteria에 대한 효용가능성에 대해서는 아직까지 광범위하게 연구된 것이 없다. 따라서 lactic acid bacteria의 과일 및 채소류의 저장시 효과적이고 적용성이 넓은 보존제로서의 성공적인 이용을 위해서 식품저장과 lactic acid bacteria에 대한 특성, lactic acid bacteria의 대사산물, lactic acid bacteria의 안정성 등을 고려하여 과일 및 채소의 식품성분 및 구성요소와 미생물의 생육저해효과가 있는 대사산물과의 관계에 대한 많은 연구의 수행이 과일 및 채소제품에서 lactic acid bacteria의 식품보존제로서의 이용가능성을 평가하기 위해 필요한 점으로 사료된다.

• 한국동물위생학회지
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• 제40권2호
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• pp.119-131
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• 2017

Among different types of spoilage, microbial contamination can cause feed decomposition, which results in decreases in feed intake and productivity, infection, and breeding disorder. During the storage time, various microbes have a chance to inoculate with depreciation of feed and to infect the animals. We investigated bacteria that inhabit diverse feed ingredients and complete feed which have been stored for a few months. We isolated and identified 30 genera and 62 species of bacteria. Among these 62 species, 21 species were of non-pathogenic bacteria, 18 species were of pathogenic bacteria, 9 species were of opportunistic pathogens, and 14 species were of unknown bacteria. Pantoea allii and 24 species showed proteolytic enzyme activity. We also confirmed that 6 species including Pseudomonas psychrotolerans showed ${\alpha}$-amylase activity, and 29 species including Burkholderia vietnamiensis showed cellulase activity. Microbacterium testaceum and 3 species showed resistance to Ampicillin, Kanamycin, Streptomycin, Gentamicin, Carbenicillin, and Erythromycin ($50{\mu}g/mL$). Using mealworm larvae (Tenebrio molitor L.) as a model for pathogenicity, we confirmed that 8 species including Staphylococcus xylosus had pathogenicity for mealworm larvae. Especially, Enterobacter hormaechei, Staphylococcus xylosus, and Staphylococcus hominis were reported as being pathogenic for humans. This research suggests that hygienic management of animal feed is essential because beneficial and harmful bacteria can inhabit animal feed differently during storage and distribution.

• Journal of Applied Biological Chemistry
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• 제50권4호
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• pp.239-243
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• 2007

Effects of aqueous chlorine dioxide ($ClO_2$) treatment on the microbial growth and the quality of iceberg lettuce during storage were examined. Lettuce samples were treated with 0, 5, 10, and 50 ppm of $ClO_2$ solution and stored at $4^{\circ}C$. Aqueous $ClO_2$ treatment significantly decreased the populations of total aerobic bacteria, yeasts and molds, and coliforms on the shredded lettuce. Fifty ppm $ClO_2$ treatment reduced the initial populations of total aerobic bacteria, yeasts and molds, and coliforms by 1.77, 1.34, 1.10 log CFU/g, respectively. Aqueous $ClO_2$ treatment caused negligible changes in the Hunter color L, a, and b values during storage. Sensory evaluations exhibited that there were no significant changes among treatments. These results indicate that the aqueous $ClO_2$ treatment can be useful in improving the microbial safety of the iceberg lettuce during storage and extending the shelf life.

• Preventive Nutrition and Food Science
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• 제12권4호
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• pp.284-288
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• 2007

Effect of aqueous chlorine dioxide $(ClO_2)$ treatment on the quality change of fresh ginseng during storage was examined. Fresh ginseng samples were treated with 0, 50, and 100 ppm of $ClO_2$ solution, respectively, and stored at $4^{\circ}C$. Microbiological data of the fresh ginseng after $ClO_2$ treatment revealed that the populations of total aerobic bacteria, and yeast and mold were significantly reduced with the increase of $ClO_2$ concentration. In particular, the populations of total aerobic bacteria, and yeast and mold in the fresh ginseng decreased by 2.1 and 1.2 log CFU/g at 100 ppm $ClO_2$ treatment, respectively. Aqueous $ClO_2$ treatment improved the color of the fresh ginseng during storage, but there was no significant difference in weight loss during storage among treatments. Sensory evaluation results represented that the qualities of the fresh ginseng treated with aqueous $ClO_2$ during storage were better than those of the control. These results clearly indicate that aqueous $ClO_2$ treatment could be useful in decreasing the microbial growth and extending the shelf life of fresh ginseng.

• Food Science and Biotechnology
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• 제18권3호
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• pp.636-640
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• 2009

The effect of post-cut vanillin treatment at high concentrations on changes of quality and microorganism in fresh-cut apples was studied. Apples (Malus domestica Borkh. cv. Fuji) were sliced, treated by dipping in different vanillin solution, 0, 40, 80, and 120 mM, packed in polyethylene bag, and then stored for up to 3 weeks at $4^{\circ}C$. Changes in total aerobic bacteria, yeast and molds, browning, soluble solids, and titratable acidity during storage were investigated. Growth of total aerobic bacteria throughout storage was strongly inhibited by vanillin regardless of treatment concentrations. Growth of yeast and molds was inhibited by vanillin of all concentrations until 2 weeks of storage. Levels of browning index, soluble solids, and titratable acidity were not significant difference among the treatment conditions until 2 weeks of storage. However, when stored for 3 weeks, browning index increased more at 80 or 120 mM vanillin, while soluble solids and titratable acidity more be decreased by 120 mM vanillin as compared with other treatment conditions. These results show that the usage of vanillin in processing of fresh-cut apples had a limitation for maintaining quality.

• 한국양봉학회지
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• 제34권4호
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• pp.325-328
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• 2019

We investigated the food storage stability of propolis extracts using homemade meatballs. Propolis extracts were prepared by using the ethanol extraction method. After making the meatballs, propolis was mixed into the meatball materials and egg water with a final concentration of 1% v/v. Microbial cultivation results showed that the cultivation of Staphylococcus aureus, which is one of the food poisoning bacteria, was reduced by more than 90% and the period of storage was 1.5 times longer. Also, it was observed to be effective when propolis was added to meatballs, it was even more effective when propolis was mixed with egg water. Thus, propolis extracts may be a useful ingredient for food storage stability due to its anti-microbacterial function.

• 디지털융복합연구
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• 제12권8호
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• pp.283-288
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• 2014

석유 제품 지하 저장 공동의 지하수 수질은 공동 인근 매립지 수질의 영향을 받는다. 매립지 주변의 지하수 수질 분석 결과, 시료의 반 정도에서 지하공동 수질에 영향이 미미한 농도의 As, Cu 및 Pb가 검출되었으며, Cd, Hg, $Cr^{6+}$, $CN^-$, TCE, PCE 및 Pheno은 검출되지 않았다. $COD^{Mn}$의 농도는 모든 시료에서 $8.0mg/{\ell}$이하로 유기물질에 의한 지하수 오염은 거의 없는 것으로 분석되었다. 1차, 2차 미생물 분석결과 총박테리아는 각각 $94.84{\times}10^4cells/{\mu}g/m{\ell}$과 $146.26{\times}10^{-4}cells/{\mu}g/m{\ell}$이고 황산환원 박테리아는 $2cells/m{\ell}$이하로 분석되어 지하공동의 수질에 영향이 미미할 것으로 분석되었다. 저장 공동 인근 지역의 지하수 수질 분석은 공동의 수리 지질의 안정성을 향상시키기 위하여 지속적인 조사와 관리가 필요할 것으로 판단된다.