• Food Science and Preservation
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• v.15 no.4
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• pp.606-611
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• 2008

Myungran Jeotkal, Korean fermented seafood, and its ingredients(hot red pepper powder, ginger, garlic, and seasoning mix) were irradiated with 0, 0.5, 1.0, 2.0, and 5.0 kGy of gamma rays and stored at 4C for 4 weeks to determine changes in microbiological and sensory characteristics. Water activities of Myungran Jeotkal, hot red pepper powder, ginger, garlic, and seasoning mix were 0.89 0.56, 0.98, 0.99, and 0.07, respectively. Myungran Jeotkal was observed to be initially contaminated. Total aerobic bacteria, yeast and mold, and coliform levels were 6.7, 4.3, and 3.6 log CFU/g, respectively. Irradiation at 2 kGy afforded approximately a 4 log reduction in total aerobic bacteria, and a 3 log drop in both yeast and mold levels and coliform bacteria(P<0.05). No viable microbial cells were detected in Myungran Jeotkal after 5 kGy of irradiation(at a detection limit of 101 CFU/g). The total aerobic bacterial level in red pepper powder was 6.3 log CFU/g and this component, of the tested ingredients, contributed most to the microbial contamination of Myungran Jeotkal. The initial count of total aerobic bacteria, 6.3 log CFU/g, was significantly reduced to 4.5 log CFU/g after irradiation(P<0.05). Sensory evaluation showed that gamma irradiation of up to 5.0 kGy did not adversely affect overall acceptability of Myungran Jeotkal or its ingredients during cold storage. Therefore, gamma irradiationwas effective to extend the shelf-life of Myungran Jeotkal.

• The Korean Journal of Food And Nutrition
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• v.27 no.1
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• pp.31-42
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• 2014

This study was conducted to evaluate the effect of gamma irradiation (0.4, 0.6, 0.8, 1 and 1.5 kGy) on the microbiological, physicochemical and sensory qualities of imported orange during storage at $3^{\circ}C$ for 60 days. Total aerobic bacteria and yeast/mold counts in non-irradiated oranges were 3.59 and 3.75 log CFU/g, and those counts in irradiated oranges at 1.5 kGy were decreased by 1.75 and 2.26 log CFU/g, respectively. Moreover, those counts were decreased significantly according to a dose-dependent manner after gamma irradiation. The pH revealed no significant difference between the control and irradiated samples; however, titratable acidity was decreased significantly according to a dose-dependent manner and storage time. The vitamin C contents were decreased significantly according to a dose-dependent manner and storage time after gamma irradiation. Further, sensory evaluation testing revealed no significant difference between the control and irradiated samples, except 1.5 kGy. Samples irradiated at 1.5 kGy had the lowest values in color, sweetness, sourness, flavor, texture and overall acceptance. The results suggest that gamma irradiation was effective for ensuring microbiological safety; however, irradiated oranges at 1 and 1.5 kGy did not have good physicochemical and sensory qualities. Therefore, we can use the sample irradiated at 0.4~0.6 kGy as optimum-dose to be minimize on quality changes.

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.209-213
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• 2011

Physicochemical, microbiological and sensory characteristics were determined during storage at 15, 25, and 35$^{\circ}C$ for six months to predict shelf-life of four fried rice retort dishes. Thiobarbituric acid (TBA) values were increased significantly and pH and acid values did not show any significant differences. Microbiological contamination levels were estimated as safe. Sensory evaluation were tested over 4 points during storage period. It maintained the commercial value during the shelf-life. TBA value as an effective quality indicator was used to estimate shelf-life with Arrhenius equation. The estimated shelf-life were 1,408 days (46 months) for beef fried rice, 1,353 days (44 months) for Ham fried rice, 1,164 (38 months) days for chicken curry fried rice and 1,182 (39 months) days for bacon tuna fried rice. In conclusion, shelf-life of all four fried rice dishes was predicted as longer than three years (36 months) at room temperature.

• Korean Journal of Poultry Science
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• v.43 no.4
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• pp.235-242
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• 2016

This study was conducted to investigate the microbiological sanitation status of raw chicken meat distributed in Korea, and potential changes in chicken breast quality during storage. The microbiological sanitation status analysis of raw chicken involved studying the results of microbiological monitoring for a 5-year period (2010~2014) by the Korean Food and Drug Administration. Furthermore, the microbiological status of raw chicken meat in meat packing centers and shops in Seoul/Gyeonggi, Kangwon, and Chungcheong Provinces was investigated from July to August 2015. The total bacterial counts of chicken meat in the packaging centers and meat shop of these Provinces were below the level specified in the Korean Meat Microbiological Guideline ($1{\times}10^7$ colony forming units [CFU]/g) and showed a similar microbiological sanitation status with results of the microbiological monitoring for the analyzed 5-year period. To evaluate the relationship between quality change and microbiological level of the meat distributed in Korea, the pH and microbiological and sensory quality characteristics of the chicken breast samples during storage at $4{\pm}2^{\circ}C$were determined. On day 4, the total bacterial count of the chicken breast was 6.76 log CFU/g, which was close to the official $1{\times}10^7CFU/g$ standard, the pH was 5.96, and the overall acceptability was reduced significantly (p<0.05). In particular, the aroma score was <5, indicating that the consumer panel expressed a negative perception even though the chicken contained a lower microbial level than that specified in the Korean microbiological guideline. These results suggest that the current Korean microbiological guideline for raw chicken meat may require a stricter level of up to $1{\times}10^6CFU/g$ to satisfy both meat safety standards and organoleptic quality for consumers.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.677-683
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• 2016

To enhance the physiological activities and reduce the off-flavor of garlic in kimchi, we manufactured kimchi seasoning replaced with 25~75% black garlic, we evaluated microbiological, physico-chemical and sensory evaluation. The changes of total aerobic and lactic acid bacteria were similar between the control and the kimchi seasoning replaced with black garlic during storage periods. The lightness of the kimchi seasoning replaced with black garlic was lower than that of the control and decrease of lightness was proportional to the concentration of black garlic. The redness and yellowness of the kimchi seasoning replaced with black garlic were decreased to the concentration of added black garlic and changes of the redness in all the samples were slightly increased during storage periods. But the yellowness did not change during storage periods. The changes of pH and acidity did not differ between the control and the samples of replaced with black garlic during storage periods. The sensory parameters including taste and flavor did not differ among treatments during storage periods. But color and overall acceptance of the control and sample replaced with 25% black garlic were higher than those of the samples replaced with 50 and 75% black garlic.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.215-221
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• 2001

Mustard leaf kimchi added different ratios of pumpkin powder(P) and green tea powder(G) were investigated by measuring changes of physicochemical, microbiological and sensory characteristics during fermentation at 5℃. The pH and total acidity were changed slowly until 20 days, and then changed rapidly for 20∼40 days in all mustard leaf kimchi groups. The pH and acidity of mustard leaf kimchi added 0.5% G was the most slowly changed compared to the other groups. Reducing sugar content was highest in mustard leaf kimchi added 0.5% P at early stage of fermentation, but the reduing sugar content of this mustard leaf kimchi group was decreased more rapidly than those of the other groups during fermentation. The numbers of lactic acid bacteria and total bacteria were highest in 0.5% P added group and lowest in 0.5% G added group. The mustard leaf kimchi added 0.3% P and 0.2% G was relatively high in number of Leuconostoc sp., on the contrary low in Lactobacillus sp. compared to the other groups during fermentation. Changes of Hunter's color values, especially yellowness, and hardness were smaller in each mustard leaf kimchi added 0.5% G, and 0.3% P and 0.2% G than the other groups. Sensory scores of taste, odor and overall acceptability were highest in mustard leaf kimchi added 0.3% P and 0.2% G. Based on these results, it is suggested that mustard leaf kimchi added 0.3% P and 0.2% G was the best group among mustard leaf kimchi groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.990-997
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• 1995

Effect of preparation method on Yulmoo kimchi(watery kimchi prepared with Yulmoo, leaf radish) fermentation was investigated by measuring physicochemical, microbiological and sensory properties for 20 days. Yulmoo kimchi was fermented at 4$^{\circ}C$ after keeping at room temperature(27$\pm$0.5$^{\circ}C$) for 8 hours. Four types(A, B, C, D) of Yulmoo kimchi were prepared. Sample A was made without wheat flour paste and red pepper powder and sample B was made with wheat flour paste. Sample C was made with red pepper powder, and sample D was made with wheat flour paste and red pepper powder. pH was slowly lowered and stabled after 10 days in all samples. Total acid content increased in all samples. Reducing sugar content initially increased and decreased thereafter. Especially, reducing sugar content of sample B increased in the early stage of fermentation and maintained initial reducing sugar content after 20 days. Total vitamin C content reduced during fermentation in all samples. Especially initial total vitamin C content of sample D increased more than those of other samples relatiely. Lightness and yellowness showed no difference, but on the other hand redness increased gradually in all samples. The number of lactic acid bactgeria reached maximum value in 10~13 days with the total cell numbers and gradually decreased thereafter in all samples. The number of lactic acid bacteria and total cell number of sample D was much more than those of any other samples. As a result of the sensory evaluation, Yulmoo kimchi showed significant difference in all characteristics. Sample D showed the highest scores in all characteristics before 10 days of fermentation. However, after 10 days sample B showed the highest scores.

• Journal of Applied Biological Chemistry
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• v.54 no.4
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• pp.303-308
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• 2011

To develop food and organoleptic quality of gochujang 0, 3, 4, and 5% of sweet persimmon powder were added to Korean traditional red pepper paste during fermentation and microbiological and organoleptic characteristics were investigated. The total bacteria count of the gochujang tended to increase slowly until a level of $10^8$ CFU/g with increasing fermentation time. There was no significant difference (p <0.05) between the control and the treatment during fermentation. The number of yeast and mold was $10^4-10^5$ CFU/g during fermentation. Sensory evaluation after 30, 60, and 90 days of fermentation showed that addition of sweet persimmon powder to the gochujang did not affect its color, but the level of sweetness and umami, increased as additional level of sweet persimmon powder increased. In the overall acceptabilty, there was no significant difference (p <0.05) until 30 days of fermentation and the gochujang added with 4% sweet persimmon powder showed the highest organoleptic value. And it showed high score in sweetness, umami and overall acceptability at the end of fermentation. The results indicated that 4% additional level of sweet persimmon powder was the best making gochujang.

• Microbiology and Biotechnology Letters
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• v.50 no.3
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• pp.361-374
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• 2022

For this study, we designed and produced mulberry low-fat ice cream supplemented with synbiotics (MLF-ISS). The sensory characteristics and physical, chemical, and microbiological qualities of MLF-ISS were then determined. Mulberry juice inoculated with or without probiotic (Lactobacillus plantarum TISTR 926 and Saccharomyces boulardii CNCM I-745) was also tested at 37℃ for 24 h to determine probiotic growth rate, pH, total anthocyanin content (TAC), total phenolic content (TPC), and antioxidant activity (AA). Only the TAC of mulberry juice inoculated with S. boulardii CNCM I-745 increased considerably (p < 0.05) among these parameters. MLF-ISS was produced with varied mulberry fruit concentrations (0, 10, 20, 30, or 40%) (w/w). The MLF-ISS prepared with 30% mulberry fruit (w/w) (30-MLF-ISS) had a higher score in appearance, color, and sweetness (p < 0.05) when sensory qualities were measured using the 9-point hedonic scale method. In the CIE lab system (L^*, a^*, b^*), the color values of 30-MLF-ISS were 27.80 ± 0.26, 12.99 ± 0.59, and 1.43 ± 0.05, respectively. The 30-MLF-ISS was also subjected to a proximate analysis. The melting rate of 30-MLF-ISS was 0.29 ± 0.03 g/min and the time it took for the first drop to fall was 37.00 ± 7.00 min. TAC, TPC, and AA of 30-MLF-ISS were observed to alter significantly (p < 0.05) during varied intervals of storage at - 18℃ (0, 30, and 60 days). The viability of probiotics in 30-MLF-ISS slightly decreased after storage at -18℃ for 8 weeks, but remained about 6 log CFU/g. During storage at -18℃ for 0 and 120 days, no pathogenic bacteria were detected in 30-MLF-ISS. These findings show that 30-MLF-ISS has nutritional and functional value, is free of foodborne pathogenic bacteria, is safe for consumers' health, and is suitable for application in the ice cream and related food industries.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.477-490
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• 2018

This study investigated the changes in the quality of doenjang (a fermented bean paste) with the addition of Sea tangle Saccharina japonica powder fermented by lactic acid bacteria (FSP). Doenjang was prepared without or with FSP and with various amounts of doenjang (0, 0.25, 0.5, 1 and 3% by volume), and fermented at $25^{\circ}C$ for 12 weeks. After 12 weeks, the antioxidant activity, microbiological characteristics, and physicochemical parameters were examined. We detected no significant differences in the color profiles. However, following the addition of FSP to doenjang, the amino nitrogen content and antioxidant properties were enhanced. Furthermore, the FSP-doenjang contained higher levels of ${\gamma}$-aminobutyric acid (297.55-300.03 mg/100 g), a biofunctional ingredient. These results suggest the potential for developing a traditional Korean fermented food with enhanced antioxidant activity and ${\gamma}$-aminobutyric acid content using FSP.