• Journal of Food Hygiene and Safety
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• v.1 no.2
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• pp.133-141
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• 1986

Gamma irradiation as a new physical treatment was applied to comparative researches with a conventional chemical fumigant on the microbiologicai and physicochemical qualities of selected agricultural products such as powdered hot pepper soybean paste,. oyste.mushroom powder, carrot flake, and raw sesame. The microorganisms contaminated in the sample, including total bacteria, thermophiles, acid tolerant bacteria, fungi, osmophilic molds and coliforms were sterilized with irradiation doses of 7-10 kGy, while ethylene oxide (E.O) fumigation proved insufficient for the destruction of them. An optimum dose of irradiation was less detrimental than E.O. fumigation to the physicochemical properties of the sample. Sensory evaluation after three months of storage at room temperatures showed that the overall acceptability of irradiated sample was higher than that of the non treated control as well as E.O. fumigated samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1867-1872
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• 2010

Microbe and quality changes of vacuum-packaged ready-to-eat lettuce were analyzed. While the vacuumpackaged lettuce after chlorine sanitizer were stored at $5^{\circ}C$, $15^{\circ}C$, and $25^{\circ}C$ for 7 days, viable numbers of total aerobic bacteria (TAB), coliform, E. coli, food-borne pathogens and lactic acids bacteria (LAB) were counted with gas production and sensory evaluation. Before the storage, only TAB of 2 log CFU/g and coliform of 1 log CFU/g were detected and LAB was not detected. TAB, coliform and LAB increased by 1 log CFU/g at $5^{\circ}C$ for 7 days without any detection of the pathogens. Sensory evaluations for off-flavour and crispness dropped to half the best value at 5 day storage. TAB and coliform increased by 3 log CFU/g and 2 log CFU/g, respectively, but LAB grew very actively by 4 log CFU/g under anaerobic environment and only B. cereus were detected after enrichment of the lettuce at $15^{\circ}C$ for 3 days. The evaluations for off-flavour and crispness were half the best value for 3 days. However, TAB and coliform increased by 3 log CFU/g, 1 log CFU/g, and 4 log CFU/g, respectively only at 1 day storage under $25^{\circ}C$. Also B. cereus were detected after enrichment and the sensory evaluation were half the best value within 1 day storage. Therefore, preservation at the lowest temperature possible is required for growth inhibition of the bacteria contaminated in the lettuce. Interestingly, LAB among them grew most actively under the anaerobic condition and the adulteration of lettuce might be closely related with the growth of LAB.

• Journal of Food Hygiene and Safety
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• v.31 no.6
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• pp.414-419
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• 2016

The aims of this study were to investigate microbial contamination levels and to survey sanitation management between Good Agricultural Practices (GAP) and non-GAP farms of lettuce and cucumber. The samples (lettuce, cucumber, soil, agricultural water, gloves, and packing plastic bag) were tested to analyze sanitary indicator bacteria (total aerobic bacteria, coliforms and Escherichia coli) and major pathogenic bacteria (Staphylococcus aureus, Bacillus cereus). In the lettuce farms, the contamination levels of total aerobic bacteria and coliforms in GAP farms were little lower than non-GAP farms or similar. Staphylococcus aureus and Bacillus cereus in soil and agricultural water of GAP farms were detected at higher levels than non-GAP farms in soil and agricultural water. In the case of cucumber farms, levels of total bacteria and Bacillus cereus in soil and total bacteria and coliform in gloves of GAP farms were higher than those of non-GAP farms, and other bacteria contamination levels in collected samples were similar. These results indicate that agricultural products produced from GAP farm still exhibited potential microbial risks. According to the field survey, a sanitation management in GAP farms was insufficient. These results could be useful as basic data to suggestion of plan for preventing microbial contamination and to improvement of GAP certification.

• Food Science of Animal Resources
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• v.40 no.3
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• pp.362-376
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• 2020

Rabbit meat bekasam is a traditional fermentation product from Indonesia. This study aimed to determine the chemical and microbiological characteristics of rabbit meat bekasam during the fermentation process in order to isolate, characterize (in vitro and in vivo), and identify lactic acid bacteria (LAB) as the probiotic candidate. The chemical contents of bekasam on 7-day fermentation were investigated in explorative and experimental methods in a completely randomized design. A proximate analysis reported a decrease in the moisture content, fat and carbohydrate content, and an increase in protein content. Also, lactic acid content was increased from 0.48% to 1.12%, and pH was decreased from 5.3 to 4.3. Other properties indicated different values, such as bacteria (2.75×10⁶ to 4.45×10⁷ CFU/g), total LAB (3.82×10⁶ to 4.67×10⁸ CFU/g), total yeast (9.89×10⁶ to 3.82×10⁸ CFU/g) and total mould (4.34×10¹ to 4.86×10³ CFU/g). The experiment produced nine LAB isolates, including two probiotics subjected to further 16S rRNA gene analysis, which indicated that Lactobacillus buchneri was the potential probiotic isolate. After being tested on BALB/c mice, L. buchneri could improve the immune system by inhibiting the growth of Coliform and Salmonella.

• Food Science and Preservation
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• v.18 no.5
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• pp.786-794
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• 2011

To investigate the sanitary-quality level of commercial kimchi in South Korea, the pH, acidity, and microbial-flora changes in the kimchi were determined. Samples of kimchi produced by three different manufacturers (a small grocery store, a small/medium-sized enterprise, and a large food company) were collected. Freshly made kimchi was purchased and fermented at $10^{\circ}C$ for 10 days. The pH of the commercial kimchi on the purchased day was approximately pH 5.8, and that on the $10^{th}$ day of fermentation was ${\simeq}pH$ 4.1. The kimchi purchased from a large company showed a more rapid decline in pH level during fermentation. The saltiness of the kimchi purchased from a medium-sized company was slightly higher than those of the other commercial kimchi samples. The saccharinity index of the kimchi produced by a small grocery store was higher than those of the other samples, and its value deviation was also higher than those of the other commercial kimchi samples. A higher total viable-cell count and a higher lactic-acid bacteria (LAB) count were detected in the kimchi from the large food company at the beginning of fermentation compared to the samples of the two other kimchi manufacturers. The highest cell numbers of gram-positive bacteria (except LAB) and coliform bacteria were detected from the small-grocery-store kimchi, but the coliform bacteria count gradually decreased during fermentation although such bacteria were still detected until the $10^{th}$ day of fermentation. In contrast, coliform bacteria were not detected in the samples from the medium-sized and large food companies. Yeast, which is detected in over-ripened kimchi, was detected in the unfermented kimchi from the small grocery store, which had a below-0.36% acidity level. The gram-positive bacteria (except LAB) that were detected in all the tested commercial kimchi samples were determined to be Bacillus spp., and the gram-negative bacteria were determined to be Escherichia coli, Enterobacter spp., Sphingomonase spp., and Strenophomonas spp. The proportions of all the aforementioned bacteria in the kimchi samples, however, were different depending on the samples that were taken. These results indicate that a more sanitary kimchi production process and a more systematic kimchi production manual should be developed to industrialize and globalize kimchi.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.628-633
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• 2012

This study investigated the washing efficiency of electrolyzed water for the removal of microorganisms and pesticide residues from Chinese cabbage. Initial total bacteria and coliform counts were 6.64 and 3.56 log cfu/g respectively. After washing, total bacteria count of tap water (TW) were 5.97 log cfu/g and low alkaline electrolyzed water (LAlEW) and strong acidic electrolyzed water (SAcEW) were 1.63-4.67 log cfu/g. Especially SAcEW-100 was found to the most effective method of washing the cabbages. After washing, the coliform count was dramatically reduced. The removal rate of pesticide residues by NaClO treatment (36.93-50.13%) was greater than that of TW treatment (32.28-38.46%). The removal rate of LAlEW-100 and SAcEW-100 was 63.79 and 78.30% respectively, and was higher than those of TW and NaClO treatments. The vitamin C content of the Chinese cabbages after all treatments did not differ significantly. Consequentially, the electrolyzed water was found to be effective to remove bacteria and pesticide residues from Chinese cabbage without affecting quality.

• Food Science and Preservation
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• v.23 no.4
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• pp.516-521
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• 2016

The characteristics and quality changes of sauces containing different concentrations (5, 10, and 15%) of fermented Oenothra biennis juice (FOBJ) were studied for its potential as a new meat seasoning suace. pH of the seasoning sauce was ranged from 5.23 to 5.37. Sugar content of seasoning sauces increased decreasing on increase of FOBJ concentration while the color (L, a, b) decreased. DPPH radical scavenging ability and TBARS values of the seasoning sauce was increased significantly by the addition of FOBJ (p<0.05). The total bacteria number of the seasoning sauces was approximately 3 log CFU/g while coliform bacteria were not detected in all tested sauces. The sauce containing 5% FOBJ showed the highest value in taste, color, overall acceptability among all tested sauces. The pH and titratable acidity of the meat seasoning sauces was not changed significantly during 25 days at $10^{\circ}C$. The total bacteria number of the seasoning sauces was steadly 3.62~3.83 log CFU/g for 25 days at $10^{\circ}C$. The number of coliform was not detected during storage periods. These results suggested the possibility of development of new meat seasoning sauce containing FOBI.

• 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.43 no.5
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• pp.784-790
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• 2014

This study was designed to establish the shelf-life of sea tangle drink. Quality changes, including pH, total acidity, color, sensory evaluation, total aerobic bacteria, and coliform, were measured periodically in sea tangle drink kept at 15, 25, and $37^{\circ}C$ for 8 months. The pH level and total acidity did not remarkably change during the storage period regardless of storage temperature. In terms of color, lightness did not change during the storage period, whereas redness decreased. Yellowness did not change at $15^{\circ}C$ during the storage period, although it increased at 25 and $37^{\circ}C$ at 8 months. Color difference (${\Delta}E$) value was the lowest at $15^{\circ}C$ (12.14), followed by $25^{\circ}C$ (12.57) and $37^{\circ}C$ (14.43). During the storage period, total aerobic bacteria and coliform were not detected. There were no changes in appearance, smell, taste, texture, and overall acceptability of sea tangle drink (not exceeding 3 points) throughout the entire storage period. By using correlation coefficients, color value was selected as an indicating parameter for the shelf-life establishment of sea tangle drink. Based on the forecasted distribution day by annual temperature, the shelf-life of sea tangle drink based on color with the highest correlation coefficient was predicted as 27.10 months.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.2
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• pp.188-192
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• 1984

In order to investigate the hygienic status of commercial red pepper powder, one sample was directly prepared from raw red pepper which was purchased at market and the other one was a commercial red pepper powder. They were used for the investigation upon the status of microbial contamination, effect of irradiation for sterilization and physicochemical changes during 3 months of storage. Total bacterial counts of commercial red pepper powders were 3.83 to $6.68{\times}10^6$ per gram and coliform group was shown to be positive in some products. Total bacteria and coliform group were sterilized by the irradiation of 9 kGy and 3 kGy, respectively and no microorganisms were grown up until 3 months of storage at room temperature. The $D_{10}$ values of total viable bacteria in red pepper powders were 1.52 to 1.58 kGy. Chemical components such as moisture, total and reducing sugars were slightly decreased during the storage period. The contents of capsanthin and capsaicin were partly affected by the high dose irradiation but the difference between unirradiated and irradiated groups was diminished with the elapse of storage period.