• 한국식품조리과학회지
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• 제17권6호
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• pp.565-570
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• 2001

본 연구에서는 쇠비름을 메탄올로 추출하여 식품의 부패나 식중독성을 유발하는 세균과 곰팡이에 대한 추출물의 항균활성을 검토하고 그들의 최소생육저해농도를 결정하였으며 쇠비름 추출물의 구성성분과 함량을 분석하였다. 쇠비름은 특히 P. citreonigrum 균주에 대해 매우 높은 항균효과를 보였고 S aureus, K. pneumoniae에 대해서는 benzoic acid에 상응할 만한 항균효과를 나타내었다. 쇠비름 메탄올 추출물은 200mg/$m\ell$ 농도에서 S. aureus와 P. citreonigrum의 생육을 억제하였고, 250 mg/$m\ell$ 농도에서 K. pneumoniae의 생육을 억제하였으며, 300 mg/$m\ell$ 농도에서 P. aeruginosa와 E. coli의 생육을 억제하였다. 따라서 이들 균주에 의한 식품의 부패 및 식중독이 우려되는 식품의 항균제로서 쇠비름의 사용 가능성을 볼 수 있었다. 쇠비름 메탄올 추출물의 분석결과 전체 147가지 성분이 분석되었으며 acid 및 ester류가 41.06%로 추출물의 가장 많은 부분을 차지하고 있었다. 또한 세균, 곰팡이, 효모와 같은 미생물에 항균활성을 나타내는 것으로 보고되어 있는 2,3-dihydro-benzofuran, 4-hydroxy-3-methoxy- benzoic acid와 4-hydroxy benzeneethanol 등의 성분들이 검출되었다.

• 동아시아식생활학회지
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• 제22권5호
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• pp.692-700
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• 2012

The antibacterial activity of the ethanol extract of Cornus officinalis against some bacteria related to foodborne illness and food spoilage was investigated. In the case of the disc diffusion assay, clear zones due to the inhibition of proliferation by Cornus officinalis extract were 8.5~18.3 mm at $4,000{\mu}g/disc$. The inhibitory effect of Cornus officinalis was as follows: Escherichia. coli ${\geq}$ Listeria monocytogenes ${\geq}$ E. coli O157:H7 > Bacillus cereus > Staphylococcus aureus > Pseudomonas aeruginosa > Salmonella typhimurium. In addition, the MIC of Cornus officinalis extract toward B. cereus was the lowest at 1,000 ppm. The extract inhibited the growth of E. coli, L. monocytogenes, E. coli O157:H7, and Bacillus cereus throughout the growth stage. However, the growth of P. aeruginosa, S. aureus, and S. typhimurium was only inhibited by the extract during the lag phase. The constituents of all cells tested were released, especially E. coli and E. coli O157:H7. Observation of the cells using SEM demonstrated a morphological change and disruption of cells in response to treatment with Cornus officinalis extract. Based on these findings, the ethanol extracts of Cornus officinalis showed strong antimicrobial activity against all tested bacteria, indicating that Cornus officinalis can be a useful natural antimicrobial reagent.

• 한국포장학회지
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• 제18권1_2호
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• pp.33-38
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• 2012

흑미를 첨가하여 제조한 기능성 찐빵에 변형기체포장으로 적용하여 저장성에 미치는 영향을 살펴보았다. 흑미 첨가 찐빵은 미생물적으로 매우 민감하여서 쉽게 부패될 수 있는 특성을 가지고 있으며, 이를 억제할 수 있는 변형기체 포장이 저장성 향상과 유통기한 연장에 기여할 수 있는 것으로 확인되었다. 미생물적 품질과 관능적 품질에 근거하여 각 포장조건 별 저장수명은 함기 포장에서는 5일 미만, 질소 포장에서는 5일, 이산화탄소 60%/질소 40% 포장에서는 8일, 이산화탄소 100% 포장에서는 15일로 설정할 수 있었다. 하지만 이산화탄소 포함 변형기체 조건에서도 노화에 의한 texture 변화는 계속 진행되므로, 이러한 저장수명 연장에의 변형기체 포장의 적용은 찐빵의 재가열 등의 상황에서 이루어져야 할 것으로 판단된다.

• 한국식품과학회지
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• 제22권2호
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• pp.116-122
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• 1990

두부의 응고제와 침지액을 달리하여 저장 중 침지액의 미생물상과 이화학적인 변화를 검토하였다. 두부는 HAc로 응고시키는 것이 $CaCl_2$보다 저장성 향성에 효과적이었고 $CaCl_2$로 제조한 두부는 $30^{\circ}C$에서 15-17시간만에 부패가 시작되어 세균수는 $10^7cells/ml$에 달하였다. 침지액은 0.1% HAc용액이 3% NaCl 용액이나 0.1% K-sorbate용액보다 두부저장에 효과적이었다. 침지액의 탁도는 두부가 부패함에 따라 비례적으로 증가하였으며 3% NaCl이나 0.1% K-sorbate 용액에 침지할 때 탁도의 증가는 심하였다. 두부의 부패가 진행될수록 침지액의 적정산도와 아미노태 질소량은 증가하였으며 pH는 1-2일 후에 증가하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제33권7호
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• pp.1103-1112
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• 2020

Objective: To measure whether a microbial additive could effectively improve the fermentation quality of delayed-sealing (DS) silage, we studied the effects of inoculants of lactic acid bacteria (LAB) and cellulase enzyme on microbial populations, ensiling characteristics, and spoilage loss of DS silage of Napier grass in Africa. Methods: Quick-sealing (QS) and DS silages were prepared with and without LAB (Lactobacillus plantarum) inoculant, cellulase enzymes, and their combination. The QS material was directly chopped and packed into a bunker silo. The DS material was packed into the silo with a delay of 24 h from harvest. Results: In the QS silage, LAB was dominant in the microbial population and produced large amounts of lactic acid. When the silage was treated with LAB and cellulase, the fermentation quality was improved. In the DS silage, aerobic bacteria and yeasts were the dominant microbes and all the silages were of poor quality. The yeast and mold counts in the DS silage were high, and they increased rapidly during aerobic exposure. As a result, the DS silages spoiled faster than the QS silages upon aerobic exposure. Conclusion: DS results in poor silage fermentation and aerobic deterioration. The microbial additive improved QS silage fermentation but was not effective for DS silage.

• 한국자원식물학회지
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• 제23권5호
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• pp.430-435
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• 2010

본 연구는 천연 식품보존료 개발의 일환으로 한약 재료로 이용되고 있는 개머루덩굴을 에탄올로 추출하여 식품부패 및 병원성 미생물에 대한 항균활성을 조사하였다. 개머루덩굴 에탄올 추출물은 식품부패 및 병원성 미생물에 대해 농도 의존적으로 항균효과를 보였으며, 그 중에서 Escherichia coli O157:H7 균에 대해 가장 높은 항균효과를 보였다. 또 개머루덩굴 에탄올 추출물이 식중독 유발세균의 성장에 미치는 효과를 검정하기 위해 Salmonella typhimurium, Yersinia enterocolitica, Staphylococcus aureus, Escherichia coli O157:H7 균들의 배양액에 개머루덩굴 에탄올 추출물의 농도를 250, 500, 1,000, 2,000 mg/L 각 농도별로 첨가하여 생육을 조사한 결과 250 mg/L까지는 대조군과 별 차이를 보이지 않았으나 500 mg/L 이상에서는 유의적인(p<0.05) 감소를 관찰할 수 있었다. 본 연구결과는 개머루덩굴 에탄올 추출물이 식중독을 유발시키는 세균에 대하여 우수한 항균작용을 나타내고 있으며, 따라서 개머루덩굴이 효과적인 천연보존료로서 이용될 수 있음을 시사하고 있다.

• 한국식품영양과학회지
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• 제28권5호
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• pp.997-1002
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• 1999

The aim of the present study was to investigate effects of food preservative addition and changes in composition of herb extract product on the growth of spoilage yeast, Zygosaccharomyces sp. Herbs such as Panax ginseng, Cinnamomum cassia, Lycium chinense, Zyzyphus juiuba and Jingiber officinale were altogether put into water and essence was extracted at 80oC, and then the extract was concentrated at 75oC. The herb extract product was made by adding vitamins, amino acids and honey to the concentrated herb extract. The amount of gas produced from the herb extract product was increased as inoculated cell number increased but decreased as Brix concentration increased. Gases were produced in small amount when incubation was made at 4oC but large amounts of gases were produced at 25 or 40oC of incubation. The gas production and growth of Zygosaccharomyces sp. were measured after browning reaction was induced by heating at 85oC for 12 hours. It appeared that heating treatment did not induce any significant change in the gas production and growth of the cell. The effects of addition of various sugar to the herb extract produce were also invesigated. Amounts of gas production were in the order of glucose>sucrose>oligosaccharide>stevioside. The viable cell count was measured as 6.0$\times$107 CFU/g when glucose was added to the herb extract product. The viable cell counts were 5.0$\times$106, 3.0$\times$103, and 3.0$\times$102 CFU/g in sucrose, oligosaccharide and stevioside added herb extract product, respectively. The amount of gas production from the herb extract product was remarkably reduced by addition of such food preservatives as sodium benzoate and DF 100. TLC(thin layer chromatography) chromatogram of the herb extract showed stability of the herb extract in the above treatments.

• 한국식품조리과학회지
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• 제6권2호
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• pp.51-58
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• 1990

Quality deterioration of barley drink during storage was examined by measuring viable count, titratable acidity (TA), turbidity and pH of barley drinks with or without barley particles stored at temperatures of 20, 25, 30, and 35$^{\circ}C$. Qualitative analysis of organic acids in spoiled barley drink was also performed. TA of barley drink during storage increased to 0.009, 0.0095, 0.0097 and 0.020% at 20, 25, 30 and 35$^{\circ}C$, respectively. TA reached the mixima between 7 and 10 days of storage and reduced from then on. pH values followed the exactly reverse trend of TA. The rate of bacterial spoilage of barley drinks was faster when it was stored at higher temperatures. The numbers of bacteria were in the range between 9.0${\times}10^6-8.0{\times}10^8$ cells/ml depending on the storage temperatures and the different brands. Those samples with higher bacterial growths showed higher optical densities. Volatile organic acids such as acetic, formic, propionic, isobutyric, isovaleric acids were detected in addition to ethyl alcohol. Non-volatile organic acids such as pyruvic, lactic, oxalacetic, succinic, fumaric acids were detected. Among them, acetic acids were most important in their quantities. Five different kinds of spoilage bacteria were isolated and identified as Bacillus Licheniformis, Bacillus coagulans, Badillus cirulans, Bacillus stearothermophilus and Bacillus brevis, all of which were found to form endospores.

• 한국식품조리과학회지
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• 제29권3호
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• pp.267-274
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• 2013

Demand for a rice cake, a popular traditional food in Korea, is rising, but its industrial-scale production is extremely difficult due to its short shelf-life caused by starch retrogradation and microbial spoilage. By means of the sourdough fermentation technique, we attempt to develop rice cakes with a longer shelf-life. Heterofermentative lactic acid bacteria (Weissella koreensis HO20, Weissella kimchii HO22) isolated from kimchi were used to ferment wet-milled rice flour for their abilities to produce exopolysaccharides and to inhibit the microbial spoilage of rice cakes. After 24 hr of fermentation at $25^{\circ}C$, viable cell counts in rice dough increased from $10^6$ CFU/g to $10^8$ CFU/g and total titratable acidity increased from 0.05% to 0.20%, whereas pH decreased from 6.5 to 5.1. Fermented rice flour showed significantly lower peak, trough, and final viscosities as well as breakdown and setback viscosities measured by rapid viscoanalyzer. Both lactic acid bacteria showed in vitro antifungal activity against Penicillium crustosum isolated from rice cakes. The antifungal activity remained constant after the treatments with heat, proteinase K and trypsin, but fell significantly by increase of pH. Rice cakes made of fermented rice flour were found to retard mycelial growth of P. crustosum. The degree of retrogradation as measured by the hardness of the rice cake was significantly reduced by the use of fermented rice flour. The results suggest that use of fermented rice flour has a beneficial role in retarding starch retrogradation and in preventing fungal growth, hence extending the shelf-life of rice cakes.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.39-39
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• 2017

In Asia, sweet potato (Ipomoea batatas) is a very important crop for starch production. Approximately 74.3% of the total sweet potato production quantity is produced in Asia (FAO, 2014) and China is the largest producer of sweet potato. Post-harvest management is particularly important because it is difficult to maintain the quality as well as quantity of sweet potatoes. Despite the importance of post-harvest management, researches on sweet potato have been focused on production-related study such as breeding of new variety, improved techniques of cultivation, so there is limited research on storage after harvest. Curing is a normal practice after sweet potato harvest to promote wound healing and extend postharvest storage life. In Korea, harvested sweet potatoes are usually cured for 4 to 7 days at $30-33^{\circ}C$ and 80-95% relative humidity within one week. Since the optimum storage temperature of sweet potato is regarded as $15-20^{\circ}C$, additional facilities and costs are required to raise the temperature for curing. However, the majority of small farmers do not have the capacity to provide additional facilities and costs. This study was initiated to suggest a new curing method to accelerate the wound healing by applying chemical oxidation to the wound surface of sweet potato. Oxidative stress is known to play an important role in the synthesis of secondary metabolites including lignin. In addition, chemical oxidation can be applied to prevent spoilage caused by microorganisms. Powerful gaseous oxidant with excellent penetration ability and superior sterilization effect was selected for this study. Lignification, weight loss, and spoilage rate of artificially wounded sweet potatoes were investigated after oxidant fumigation. There were clear differences in morphological analysis such as lignification pattern, lignin deposition color, and continuity of lignified cell layers between oxidant-fumigated sweet potatoes and control. These results show that gaseous oxidant can be used to supplement or replace the curing practice, to improve shelf-life as well as curing cost reduction.