• Fisheries and Aquatic Sciences
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• 제26권10호
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• pp.593-604
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• 2023

Post-harvest handling and hygienic level of aquatic products significantly affect the quality and level of safety. Cold chain control is one of the determining factors for the quality of fish and the bacterial community that grows on the fish. Identification of spoilage bacteria and pathogens in aquatic products must be made because it will determine the physical and chemical quality. A molecular identification method with high sensitivity is the solution. This study aims to identify the quality of fish and bacterial communities that grow. The research procedures included sample collection, pH measurement, drip loss measurement, transportation and cold storage treatment, DNA extraction, DNA sequencing, sequence analysis, and bioinformatics analysis. The conclusion obtained from this study is that the simulation of the cold chain system applied to eastern little tuna does not significantly affect changes in the water activity value, pH, and drip loss. The insignificant change indicates that the eastern little tuna samples are still in good quality. The bioinformatics analysis showed the highest diversity and abundance of the bacterial community came from the Gammaproteobacterial class.

• 한국동물위생학회지
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• 제22권4호
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• pp.411-418
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• 1999

In this studies, the ability of chlorine and lactic acid to reduce bacterial population of the pathogenic microorganisms were examined on artificially inoculated chicken skin. About 10$^{5}$ cells of staphylococcus aureus, salmonella enteritidis, listeria monocytogenes and escherichia coli O157:H7 were inoculated in chicken skin. The contaminated samples were washed for 1 min with sodium hypochlorite solutions that contained 2, 5, 10, 20 and 50mg/$\ell$ available chlorine and counted number of the agents. Viable population were no significantly difference (p$\geq$0.05) between concentration of chlorine and strains of the pathogens. In the samples inoculated with pathogens were washed in 20mg/$\ell$ chlorine and then stored at $^5{\circ}C$ for up to 10 days, the initial counts of psychrotrophs and aerobic plate counts were 4.02 to 4.36 log cfu/$\textrm{cm}^2$ and increased slightly in course of time. But 10 days after, the pathogens were a little reduced from 3.66~4.91 log cfu/$\textrm{cm}^2$ to 2.54~4.66 log cfu/$\textrm{cm}^2$. In the case of washed skin with solution of 20mg/$\ell$ chlorine and 0.5% lactic acid then store at $^5{\circ}C$ for up to 10 days, population of psychrotrophs and aerobic plate counts on chicken skin were markedly reduced immediately after treatment, but the numbers of contaminants were slightly increased after 6 and 8 days. Specifically, numbers of St aureus, S enteritidis, L monocytogenes and E coli O157:H7 were reduced to 0.5, 0.4, 0.3 and 1.15 log cfu/$\textrm{cm}^2$ after 10 days of storage, respectively, on aerobic plate counts.

• Preventive Nutrition and Food Science
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• 제7권3호
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• pp.305-309
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• 2002

Raw soybean sprouts were tested for contamination with the following bacteria which have potential for pathogenesis or food spoilage : Salmonella spp., Escherichia coli O157:H7, Yersinia enterocolitica, Vibrio parahae-molyticus, Aeromonas hydrophila, Plesidomonas shigeloides, Pseudomonas aeruginosa, Staphylococcus aureus, Lis-teria monocytogenes, Bacillus cereus, Clostridium perfringens, Campylobacter jejuni, Erwinia spp., and Fusarium spp. Three of the above strains were isolated from the sprouts, and identified by morphological and biochemical methods including an API kit and ATB automated identification system. The isolate cultured in Cereus selective agar, a selective medium, was a Gram-positive, rod shaped, anaerobic spore former. The biochemical and culture tests revealed the following characteristics: catalase-positive, no growth on Simmon's citrate, NO₂ production and requirement of arginine for growth; the ATB automated identification system gave 99.8 % agreement for the identification of Bacillus cereus to the species level. The isolate cultured in Macconkey agar selective medium was Gram-negative, rod shaped and a gas former; the ATB-system gave 99.9% agreement for the identification of Aeromonas hydrophila to the species level. The isolate found in Pseudomonas isolation agar was Gram-negative, rod shaped, cytochrome oxidase-positive, a reducer of nitrates to nitrogen, and pyocyanin producer; the ATB-system gave 99.9 % agreement for the identification of Pseudomonas aeruginosa to the species level. These results indicate that the three bacteria species present in the soybean sprouts were Bacillus cereus, Aero-monas hydrophila, and Pseudomonas aeruginosa. Salmonella spp., Escherichia coli O157:H7, and Yersinia enter-ocolitica, which are associated with serious disease in humans, were not isolated from soybean sprouts examined in this study.

• Food Science and Biotechnology
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• 제14권4호
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• pp.461-465
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• 2005

To determine the cause of wet noodle spoilage, microorganisms isolated from wet noodles were identified and characterized. In addition, the growth inhibitory effects of organic acid mixture (OA: lactic acid 27.8%, acetic acid 12.0%, succinic acid 1.0%) and sodium dehydroacetate (SD) on the isolated strain were estimated in nutrient broth medium. The isolated strain was Gram-positive, rod shaped, motile, and spore forming. Based on physiological characteristics and the API 50 CHB-kit test results for the assimilation of 49 carbohydrates, the isolated strain was identified as Bacillus amyloliquefaciens (92.6%), which is able to degrade starch. Decimal reduction times (D-values) at 100, 105, and $110^{\circ}C$ for spores of B. amyloliquefaciens were 8.5, 5.1, and 2.5 min, respectively, and the z-value was $12.8^{\circ}C$. We estimated that B. amylo-liquefaciens isolated from spoiled wet noodles was a thermophilic species having high heat-resistance. Viable cell numbers in wet noodles and broth medium inoculated with B. amyloliquefaciens were decreased by 2-4 log cycles by combined treatment with 0.03 or 0.05% OA and 0.3% SD. These results revealed that OA combined with SD could be used as a potential agent to inhibit B. amyloliquefaciens in wet noodles.

• 한국축산식품학회지
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• 제34권5호
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• pp.591-596
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• 2014

This study evaluated the effect of sodium diacetate and sodium lactate solutions for reducing the cell count of Pseudomonas spp. in frankfurters and hams. A mixture of Pseudomonas aeruginosa (NCCP10338, NCCP10250, and NCCP11229), and Pseudomonas fluorescens (KACC10323 and KACC10326) was inoculated on cooked frankfurters and ham. The inoculated samples were immersed into control (sterile distilled water), sodium diacetate (5 and 10%), sodium lactate (5 and 10%), 5% sodium diacetate + 5% sodium lactate, and 10% sodium diacetate + 10% sodium lactate for 0-10 min. Inoculated frankfurters and ham were also immersed into acidified (pH 3.0) solutions such as acidified sodium diacetate (5 and 10%), and acidified sodium lactate (5 and 10%) in addition to control (acidified distilled water) for 0-10 min. Total aerobic plate counts for Pseudomonas spp. were enumerated on Cetrimide agar. Significant reductions (ca. 2 Log CFU/g) in Pseudomonas spp. cells on frankfurters and ham were observed only for a combination treatment of 10% sodium lactate + 10% sodium diacetate. When the solutions were acidified to pH 3.0, the total reductions of Pseudomonas spp. were 1.5-4.0 Log CFU/g. The order of reduction amounts of Pseudomonas spp. cell counts was 10% sodium lactate > 5% sodium lactate ${\geq}$ 10% sodium diacetate > 5% sodium diacetate > control for frankfurters, and 10% sodium lactate > 5% sodium lactate > 10% sodium diacetate > 5% sodium diacetate > control for ham. The results suggest that using acidified food additive antimicrobials, as dipping solutions, should be useful in reducing Pseudomonas spp. on frankfurters and ham.

• Journal of Ginseng Research
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• 제25권3호
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• pp.122-126
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• 2001

수삼을 물로 세척한 후 한 뿌리씩 연포장재 필름 주머니(ONY/LDPE/L-LDPE, 200$\times$300mm, 90$\mu\textrm{m}$)에 넣고 밀봉하여 $25^{\circ}C$, 1$0^{\circ}C$ 또는 4$^{\circ}C$에서 저장하면서 외관품질과 개체무게를 조사한 결과 수삼의 외관품질은 저장온도에 관계없이 주로 연화에 의하여 불량해졌으며 외관품질 변화 속도상수와 저장온도의 역수뿐만 아니라 개체무게 변화속도상수와 저장온도의 역수간에도 각각 5% 유의수준에서 양호한 직선관계를 나타내었다. 따라서 $25^{\circ}C$에서의 온도학대시험을 통하여 저온에서 저장중인 개별포장 수삼의 저장수명 및 개체무게 변화율을 단기간에 예측할 수 있을 것으로 판단된다.

• 한국축산식품학회지
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• 제35권4호
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• pp.421-430
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• 2015

This study was performed to investigate the possibility of the addition of mugwort herb extract (MH) and vitamin C (VC) alone (0.05%) and in combination (0.05% each) on shelf-life of seasoned pork. The combination of VC+MH demonstrated a significant reduction in thiobarbituric acid reactive substances, and volatile basic nitrogen in seasoned pork. Also, the pH values, total lactic acid concentration, lactic acid bacteria count, and the sensory properties (discoloration, flavor, and overall acceptability) of seasoned pork were not significantly affected by adding MH and/or VC. All seasoned pork were rejected by sensory panel when LAB count reached levels of 5-6 Log CFU/g, TLA concentration has been above a level of 3.6-3.9 mg lactic acid/g, and pH values ranged from 5.31-5.51 (15 d). Therefore, the findings showed that spoilage of seasoned pork does not appear to be the result of lipid oxidation, but is caused by lactic acid producing bacteria which result in sour odor.

• 한국축산식품학회지
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• 제30권1호
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• pp.49-54
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• 2010

The aim of this research was to estimate the effect of temperature and develop predictive models for the growth of total viable cells (TVC) and Escherichia coli (EC) on chicken breast under aerobic and various temperature conditions. The primary models were determined by Baranyi model. The secondary models for the specific growth rate (SGR) and lag time (LT), as a function of storage temperature, were developed by the polynomial model. The initial contamination level of chicken breasts was around 4.3 Log CFU/g of TVC and 1.0 Log CFU/g of E. coli. During 216 h of storage, SGR of TVC showed 0.05, 0.15, and 0.54 Log CFU/g/h at 5, 15, and $25^{\circ}C$. Also, the growth tendency of EC was similar to those of TVC. As storage temperature increased, the values of SGR of microorganisms increased dramatically and the values of LT decreased inversely. The predicted growth models with experimental data were evaluated by $B_f$, $A_f$, RMSE, and $R^2$. These values indicated that these developed models were reliable to express the growth of TVC and EC on chicken breasts. The temperature changes of distribution and showcase in markets might affect the growth of microorganisms and spoilage of chicken breast mainly.

• 한국식품저장유통학회지
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• 제6권2호
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• pp.239-244
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• 1999

자소잎중 물과 에탄올을 이용하여 얻은 추출물을 2종의 부패곰팡이(Aspergillus flavus KCTC 6143, Aspergillus jlavus KcrC 6961) 및 5종의 식중독세균 ( isteria monocytogenes ATCC 15313, Staphylococc따 aureus 196E ATCC 13565, Escherichia coli 0157:H7 ATCC 43895, Salmonella typhimurium ATCC 13311, Yersinia enterocolitica)에 대하여 항균효과를 조사하였다. 생육증식 저해농도를 disk method로 검색한 결과 에탄올추출물에서 그 효과가 인정되어 5종의 식중독 세균에 대하여 자소잎 에탄올 추출물을 농도별로 첨 가한 후 그 효과를 비교하였다. Gram양성균(L. monocytogenes, S. aureus)의 경우가 Gram음성균(E. coli 0157:H7, S. typhimurium, Y. enterocolitica)에 비하 여자소잎 에탄올추출물에 의한 증식억제효과가 추 출물 $1000\mu\textrm{g}$/mL 농도 첨가구에서 월둥히 컸으며 생 육증식억제효과의 크기는 L. monocytogenes, S. aureus, S. typhimurium의 순이었고, E. coli 0157:H7과 Y enterocolitica균에 대한 생육증식억제 효과는 농도첨 가별에 따라 생육증식이 비례적으로 억제되었다. 자 소잎 에탄올 추출물은 $121^{\circ}C$에서 15분간 가열처리한 후에도 항균력이 인정되었다.

• 한국식품영양과학회지
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• 제33권3호
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• pp.494-499
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• 2004

본 연구에서는 추출용매(물, 메탄올, 석유 에테르)에 따른 정향추출물의 항균성을 비교, 검토하고자 하였다. 물 추출물의 경우 E coli, S. aureus, S. typhimurium, P. aeruginosa에 대해서 항균효과를 나타내었으며 B. subtilis에서는 높은 농도에서도 항균력을 보이지 않았다. 메탄올 추출물의 경우 모든 균에서 항균성을 나타내었고, 특히 S. aureus에 대한 항균성이 매우 우수하였으며, 반면에 석유 에테르 추출물의 경우에서는 항균효과를 나타내지 않았다. 액체배지에서 정향의 생육저해 효과는 물 추출물의 경우 B. subtilis를 제외한 모든 균에서 항균력을 보였으며, 균종별로는 S. aureus보다 E. coli, S. typhimurium에서 더 강한 항균력 을 보였다. 메탄올 추출물의 생육저해 효과를 조사한 결과 모든 균에서 강한 항균력을 보였고, G(-)균보다 G(＋)균에 대한 생육저해 효과가 크게 나타났다. 반면 석유 에테르 추출물은 모든 균에 대해서 추출물의 농도에 관계없이 생육저해 효과를 보이지 않았다. 따라서 정향 추출물의 항균력은 메탄올>물>석유에테르 추출물 순이었다.