• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1843-1851
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• 2014

This study evaluated the quality characteristics and antioxidant activities of barley Doenjang (soybean paste) containing various contents (4, 12, and 20%) of kelp extracts. After 60 days of fermentation, pH, acidity, and viscosity of Doenjang were 5.80~6.86, 0.57~1.87%, and 4,913.3~9,333.3 cps, respectively, showing significant differences according to content of kelp extracts. Amino-type nitrogen contents was 902.60~921.90 mg%. For color values, L and b values increased significantly (P<0.001), whereas a value decreased slightly according to kelp extracts. DPPH radical scavenging effect ($IC_{50}$) for butylated hydroxyanisole ranged from 10.28 mg/mL to 23.23 mg/mL. DPPH radical scavenging effects of control was highest among the samples. The total polyphenol and flavonoid contents were 12.72~6.37 mg tannic acid equivalence/g, and $0.98{\sim}1.56{\mu}g$ rutin equivalence/g, respectively. Initial counts of total bacteria and lactic acid bacteria were 7.20~7.57 log CFU/g, and 4.20~4.71 log CFU/g respectively, showing significant difference according treatment and fermentation (P<0.05). In the sensory evaluation, 20% kelp extract Doenjang (5.6) showed higher overall acceptability than other samples (6.5) (P<0.01). Especially, umami taste (6.1) and texture (6.4) of 20% kelp extract Doenjang were higher than those of control (P<0.05). These results suggest that Doenjang containing kelp extracts, will be good for industrial fields.

• Food Science and Preservation
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• v.20 no.2
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• pp.141-150
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• 2013

For the investigation of the quality loss of mulberry during distribution, the deterioration rate, microorganism growth, and sensory quality of mulberry kept at 20, 10 and $0^{\circ}C$, respectively, were investigated. Based on the results, the optimum temperature for extending the freshness of mulberry was examined in the temperature range of -1.5 to $1.5^{\circ}C$. The level of mold in the mulberry kept at 20 and $10^{\circ}C$, respectively, was much higher than that kept at $0^{\circ}C$. The quality of the mulberry deteriorated seriously after two days at $20^{\circ}C$, after six days at $10^{\circ}C$, and after 12 days at $0^{\circ}C$. The marketability of mulberry as determined via sensory evaluation was much more prolonged by decreasing the keeping temperature from 20 to $0^{\circ}C$. To extend the freshness of mulberry using these results, the optimum temperature was evaluated at the range of -1.5 to $1.5^{\circ}C$ for 25 days. During storage, the changes in the color and pH of the berry were not significantly different by storage temperature, but the microbial levels and deterioration rate increased in the order of 1.5, 0, and $-1.5^{\circ}C$. In particular, the firmness of the mulberry decreased rapidly at $1.5^{\circ}C$, showing a significant difference from the others. The titratable acidity and sugar contents decreased gradually at all the applied temperatures. The anthocyanin content decreased sharply at $1.5^{\circ}C$ but gently changed at $-1.5^{\circ}C$. Through the sensory results of this study, it was adjudged that the marketability of mulberry could be maintained about 0.7 times at $1.5^{\circ}C$ and 1.3 times at $-1.5^{\circ}C$ compared with the marketability at $0^{\circ}C$, respectively.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.217-223
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• 1979

The present study was to investigate the effect of sugars on the psychrophillic spoilage in ground meat. The obtained results were summarized as follows: 1. The minimum pH values for the ground beef containing 2, 5 and 10 % glucose were 5.25, 5.15 and 4.5, respectively. For the ground pork, the respective values were 5.1, 4.45 and 4.1. 2. Total aerobes, coliform, lactic acid bacteria and lactobacillus counts per gram for the control and 2% glucose-contained ground beef after 9 days for storage at $5^{\circ}C$ were $8.3{\times}10^9vs\;6.0{\times}10^7,\;3.5{\times}10^5vs\;2.4{\times}10^3,\;5.8{\times}10^7vs\;4.7{\times}10^6$ and $3.6{\times}10^5vs\;4.2{\times}10^6$ respectively. For the ground pork, the respective values were $1.2{\times}10^{10}vs\;7.8{\times}10^8,\;3.4{\times}10^5vs\;3.1{\times}10^4,\;5.5{\times}10^7vs\;4.5{\times}10^6$ and $3.3{\times}10^5vs\;3.7{\times}10^5$. The glucose-added ground meat showed higher counts than those of the controls only in the case of lactobacillus without any apparent adverse effects. 3. The length of storage time until the depletion of added glucose was 12, 16 and 28 days for the 2, 5 and 10 % glucose contained ground beef and 9, 16 and 30 days for the ground pork, respectively. pH did not start to increase until the added glucose was depleted completely. 4. The addition of glucose extended significantly the average shelf-life of ground beef at refrigeration condition $(5^{\circ}C)$. The extended shelf-life over the control was 7, 9 and 12days for the 2, 5 and 10 % glucose contained ground beef and 8, 10 and 12 days for the respective ground porks. 5. Although the addition of disaccharides (maltose, lactose, saccharose) lowered the pH of ground meat, the extension of shelf-life as seen in glucose treatment was not affected. In fact, the higher the concentration of added disaccharides was, the greater the degree of putrefaction occurred.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.759-765
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• 2013

In this study, we investigated the quality characteristics of Sikhye, a traditional Korean drink, made with various amounts (0.5, 1, 2, and 3%) of powder from the roots of Doraji (RPD), for different storage periods (1, 3, 5, 7, 10, 13, or 15 days). The pH and Hunter's L value of Sikhye decreased with higher amounts of added RPD, while saccharinity as well as "a" and b values increased. During storage, pH and Hunter's L value of Sikhye tended to decrease while "a" and b values increased. The saccharinity of Sikhye with 0.5% and 1% RPD reached its maximum values on the tenth storage day and continuously decreased during the storage period. In contrast, the saccharinity of Sikhye with 2% and 3% RPD increased during the storage period, and had its maximum saccharinity on the fifteenth storage day. During the storage of Sikhye the total microbial cell count, typically $3.19{\sim}0.35{\times}10^2$ CFU/mL on the third storage day, was undetected in Sikhye with 3% RPD. The total microbial cell count of Sikhye without RPD increased to $1.91{\times}10^9$ CFU/mL by the fifteenth storage day, while Sikhye with 0.5, 1, 2, and 3% RPD added contained $8.43{\times}10^8$, $9.77{\times}10^7$, $2.10{\times}10^7$, and $7.21{\times}10^6$ CFU/mL, respectively. Thus, the total cell count was lower with higher additions of RPD. In sensory tests, the Sikhye control, or with 0.5% and 1% RPD added, didn't show significant differences in the texture of rice granules, plumpness of rice granules, floating of rice granules, taste, flavor, and sweetness values. The overall preference was highest (5.38) for Sikhye with 0.5% RPD, followed by the control, 1% RPD, 2% RPD and 3% RPD. In conclusion, according to preference tests, we recommended the addition of 0.5% or 1% RPD in Sikhye.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.1
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• pp.123-134
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• 2014

Identification of methods to optimize the growth of a plant community, including the capacity of the soil to further sequester carbon, is important in urban design and planning. In this study, to construct and manage an urban park to mitigate carbon emissions, soil organic carbon of varying biomass, different park construction times, and a range of vegetation types were analyzed by measuring aboveground and belowground carbon in Seoseoul Lake Park and Yangjae Citizen's Forest. The urban parks were constructed during different periods; Seoseoul Lake Park was constructed in 2009, whereas Yangjae Citizen's Forest was constructed in 1986. To identify the differences in soil organic carbon in various plant communities and soil types, above and belowground carbon were measured based on biomass, as well as the physical and chemical features of the soil. Allometric equations were used to measure biomass. Soil total organic carbon (TOC) and chemical properties such as pH, cation exchange capacity (CEC), total nitrogen (TN), and soil microbes were analyzed. The analysis results show that the biomass of the Yangjae Citizen's Forest was higher than that of the Seoseoul Lake Park, indicating that older park has higher biomass. On the other hand, TOC was lower in the Yangjae Citizen's Forest than in the Seoseoul Lake Park; air pollution and acid rain probably changed the acidity of the soil in the Yangjae Citizen's Forest. Furthermore, TOC was higher in mono-layered plantation area compared to that in multi-layered plantation area. Improving the soil texture would, in the long term, result in better vegetation growth. To improve the soil texture of an urban park, park management, including pH control by using lime fertilization, soil compaction control, and leaving litter for soil nutrition is necessary.

• Korean journal of food and cookery science
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• v.28 no.4
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• pp.391-397
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• 2012

This study was carried out to investigate commercialization of Kimchi made of cabbage (Brassica oleracea var. capitata L.) using pre-fermentation conditions. The pre-fermentation conditions were 0, 18, 24, and 28 h at $20^{\circ}C$, and then the samples were stored at $10^{\circ}C$ to assess changes in quality characteristics. A comparison of the quality characteristics during storage showed that PF24 (pre-fermented cabbage Kimchi during 24 h at $20^{\circ}C$) and PF28 (pre-fermented cabbage Kimchi during 28 h at $20^{\circ}C$) had pH 4.47 and pH 4.23 on the second day of storage, respectively. It was possible to shorten the fermentation time to less than that of PF0 (not pre-fermented cabbage Kimchi at $20^{\circ}C$), by approximately 3 days. Total acidity was 0.26 to 0.29% immediately after making the Kimchi. However, PF0, PF18 (pre-fermented cabbage Kimchi during 18 h at $20^{\circ}C$), PF24 and PF28 became well-fermented when they were stored for 8~14 days, 3~10 days or 2~3 days. The number of lactic acid bacteria increased with the passage of time in all treatment groups regardless of fermentation conditions. However, the longer pre-fermentation time became, the faster the number of lactic acid bacteria increased. Most samples showed similar results late in the storage period; 7.2~7.4 log CFU/mL. PF0 had the greatest volume change 2.1 times increase late in the storage period. The sensory evaluation showed significant differences for flavor, taste, and overall acceptability after a partial storage period. PF28 stored for 2~3 days showed excellent flavor, and PF24 and PF28 stored for 2~3 days showed the highest scores of 6.27 to 6.67. The PF24 and PF28 treated samples were appropriate for commercializing small packed cabbage Kimchi and for alleviating the expansion problem of the packing material. However, because mass commercial production requires a large number of samples to be used at once, the results should be assessed for industrial product development in the future.

• Journal of Food Hygiene and Safety
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• v.36 no.3
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• pp.271-279
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• 2021

Sweet pumpkin is rich in minerals such as calcium, phosphorus and fiber, and also contains a large amount of β-carotene, which has antioxidant effects. In this study, Makgeolli containing steaming sweet pumpkin (SP) was manufactured to enhance the antioxidant activity. To prepare the Makgeolli, SP was added in amounts of 5, 10, 20, and 30% (w/w), and the chemical (pH, total acidity, alcohol), microbiological (lactic acid bacteria, yeast) properties, and antioxidant activities (DPPH, ABTS) were examined during fermentation and storage for 9 days. The pH of SP Makgeolli was 4.00-4.23 at day 1 of fermentation, and then the pH gradually decreased as fermentation progressed, showing the lowest results at day 9 (3.28-3.52). At day 1, the total acidity was significantly increased (P<0.05) as the amount of SP (0-30%; 0.09-0.55%) and the total acidity in SP Makgeolli (1.01-1.20) was also rapidly increased by 5 days of fermentation. Alcohol content was significantly increased (P<0.05) as the amount of SP (0-30%; 4.59-5.77%) increased at day 9. The counts of lactic acid bacteria and yeast in SP Makgeolli were 8.0-8.1 and 7.9-7.8.0 CFU/mL, respectively, which was higher than SP 0% at day 9. DPPH and ABTS radical scavenging activities were significantly increased (P<0.05) as the amount of SP (0-30%; 48.29-78.97% for DPPH, 62.12-86.68% for ABTS) increased at day 9. This study suggests that Makgeolli added with SP could be potentially and commercially developed due to its superior microbiological and chemical properties, including high antioxidant activities.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.3
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• pp.223-229
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• 2022

This study was conducted to investigate the effect of packaging methods and sterilization treatment on storability and microbial control in paprika fruits. When treated with chlorine dioxide gas for 3, 6, and 12 hours and cold plasma gas for 1, 3, and 6 hours, and then packed in a carton box and stored in a 8 ± 1℃ chamber for 7 days, chlorine dioxide treated 12 hours and plasma treated 6 hours was prevented the development of E·coli and YM(yeast and mold). Accordingly, the control was treated with chlorine dioxide for 12 hours and plasma for 6 hours, packed using a carton box and 40,000 cc·m^-2·day^-1·atm^-1 OTR film (MAP), and stored in a 8 ± 1℃ chamber for 20 days. Fresh weight loss rate during storage was less than 1% in the MAP treatments, and the visual quality of the MAP treatments was above the marketability limit until the end of storage. There was no difference in the contents of oxygen, carbon dioxide, and ethylene in the film. In the case of firmness, the chlorine dioxide treatments was low, and the Hunter a^* value, which showed chromaticity, was highest in the Plasma 6h MAP treatment. Off-odor was investigated in the MAP treatments, but it was very low. The rate of mold growth on the fruit stalk of paprika was the fastest and highest in the chlorine dioxide treated box packaging treatments, and the lowest in the chlorine dioxide treated MAP treatments at the end of storage. The aerobic count in the pulp on the storage end date was the lowest in the plasma treated box packaging treatments, the lowest number of E·coli in the chlorine dioxide treated MAP treatments, and the lowest yeast & mold in the chlorine dioxide treated box packaging treatments. As a result, for the inhibition of microorganisms during paprika storage, it is considered appropriate to treat plasma for 6 hours before storage regardless of the packaging method.

• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.181-198
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• 1998

In order to determine the optimum pasteurization conditions by microwave heating(MWH) at $50^{\circ}C{\sim}70^{\circ}C$ for 30 minute compared with water bath heating(WBH) at $65^{\circ}C$ for 30minute during storage at $5^{\circ}C$, the chemical composition, microbiological changes and keeping quality were examined and the results were as follows: 1. The fat protein lactose, total solid contents of raw milk, at $50{\sim}70^{\circ}C$ for 30 min. in MWH and at 65 for $30^{\circ}C$ min. in WBH did not changed significantly during the storage at $5^{\circ}C$. 2. The pH and acidity for the raw milk untreated were 6.75 and 0.16%, and those of MWH heated and WBH milk wee 6.75~6.50 and 0.16%~0.19%, phosphatase test were negative at $61^{\circ}C$ for 20 min. at $62^{\circ}C$ for 15 min. at $63^{\circ}C$ for 10 min. at $64^{\circ}C$ for 5 min. at $65^{\circ}C$ for 5 min. in MWH and at $65^{\circ}C$ for 30 min. in WBH. 3. Whey protein content was $18.53mg/m{\ell}$ in raw milk untreated, however, those were decreased as the heating temperature increased. The proteolytic activity of treated milk by WBH(44%) was lower than that by MWH(94%). 4. Total bacteria counts were $2.8{\times}10^5CFU/m{\ell}$ in raw milk untreated, $2.8{\times}10^3CFU/m{\ell}$ at $65^{\circ}C$ for 30 min. $2.4{\times}10^3CFU/m{\ell}$ at $70^{\circ}C$ for 30 min. in MWH and $3.0{\times}10^3CFU/m{\ell}$ at $65^{\circ}C$ for 30 min. in WBH. Because total bacteria count did not increased in MWH at $65^{\circ}C$, $70^{\circ}C$ for 30 min. and $65^{\circ}C$ for 30 min. in WBH during the 10 days storaging, Also, total bacteria counts for treated milk were a most drastic decrease after $61^{\circ}C$, $62^{\circ}C$, $63^{\circ}C$, $64^{\circ}C$, $65^{\circ}C$ for 5 min. in MWH. 5. Coliform bacteria counts were $2.6{\times}10^3CFU/m{\ell}$ in raw milk untreated. There were not detected at $55^{\circ}C{\sim}70^{\circ}C$ for 30 min. in MWH and at $65^{\circ}C$ for 30 min. in WBH. Coliform bacteria counts were not detected after $61^{\circ}C$, $62^{\circ}C$, $63^{\circ}C$, $64^{\circ}C$, $65^{\circ}C$ for 5 min. in MWH. 6. Thermoduric bacteria counts were $5.2{\times}10^4CFU/m{\ell}$ in raw milk untreated, $2.0{\times}10^3CFU/m{\ell}$ at $65^{\circ}C$ for 30 min. $1.9{\times}10^3CFU/m{\ell}$ at $70^{\circ}C$ for 30min. in MWH and $2.2{\times}10^3CFU/m{\ell}$ at $65^{\circ}C$ for 30 min. in WBH. Because thermoduric bacteria counts did not increased in MWH at $65^{\circ}C$, $70^{\circ}C$ for 30 min. and $65^{\circ}C$ for 30 min. in WBH during the 10days storaging. Also, thermoduric bacteria counts were a most drastic decrease after $61^{\circ}C$, $62^{\circ}C$, $63^{\circ}C$, $64^{\circ}C$, $65^{\circ}C$ for 5 min. in MWH. 7. Psychrotrophic bacteria counts were $2.8{\times}10^5CFU/m{\ell}$ in raw milk untreated, $2.0{\times}10^1CFU/m{\ell}$ at $65^{\circ}C$ for 30 min. $2.0{\times}10^1CFU/m{\ell}$ at $70^{\circ}C$ for 30 min. in MWH and $3.0{\times}10^1CFU/m{\ell}$ at $65^{\circ}C$for 30 min. in WBH. Because psychrotrophic bacteria counts did not increased in MWH at $65^{\circ}C$, $70^{\circ}C$ for 30min. and $65^{\circ}C$ for 30 min. in WBH during the 10 days storaging. Also, psychrotrophic bacteria counts were a most drastic decrease after $61^{\circ}C$, $62^{\circ}C$, $63^{\circ}C$, $64^{\circ}C$, $65^{\circ}C$ for 5 min. in MWH.