• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.3
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• pp.220-225
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• 2010

Soybean sprouts produced at optimal temperature are placed or displayed for several days in market shelf of relatively cool temperature (ca. $13^{\circ}C$). During this period a number of changes occur including changes in color, smell, taste, nutritional quality, etc. In order to investigate the changes of these factors, soybean sprouts packed in plastic film bag (OPP+PE) were stored at the two different temperature ($3^{\circ}C$ and $13^{\circ}C$). Morphological characters, physicochemical changes and enzymes activity related to visible quality (color) of soybean sprouts were examined. The numbers of fine roots were greater and hypocotyls were longer in soybean sprouts stored at $13^{\circ}C$, although there was no significant difference in diameter, fresh weight and dry weight of hypocotyls between the two storage temperatures. Browning of hypocotyl, as an indicator of a typical deterioration in sprout quality, was highly dependent on the activity of polyphenol oxidase (PPO). Considering the low level of soluble protein in hypocotyls, the relatively higher activity of PPO suggested a critical role of PPO in stored soybean sprouts. PPO activity of sprouts stored at $13^{\circ}C$ was 2-fold higher than that of sprouts stored at $3^{\circ}C$ after 4 days. In sprouts stored at $13^{\circ}C$, the PPO activity was increased from day 0 until 6 days and since then, it was not detected. Crude protein content was increased to 30.9~35.4% based on dry weight with extended storage period. The change in crude protein was greater in sprouts stored at high temperature ($13^{\circ}C$). Total free amino acid content was increased in both temperatures. However, the changing rate of free amino acid was greater in sprouts stored at $13^{\circ}C$.

• Korean Journal of Microbiology
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• v.52 no.1
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• pp.98-109
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• 2016

The study was aimed to investigate the mixing ratio of kiwi and persimmon juices for the production of good quality wine by Saccharomyces cerevisiae Y28. Firstly, the optimum condition of rapidase treatment for the kiwi and persimmon juices was established, thereafter various mixing ratio (10:0, 9:1, 8:2, 7:3, 6:4, 5:5) of kiwi and persimmon was investigated regarding physiochemical properties and flavor compounds of wine. As the result, the optimum conditions were obtained as 0.3% rapidase for 1 h in kiwi and 0.3% rapidase for 3 h in persimmon. According to higher ration of persimmon, the pH of wines increased from 3.69 to 3.77, while the acidity of wines decreased from 2.07% to 1.51% at 14 days fermentation. The ranges of brix and reducing sugar in wines were decreased which ranges around 9.6 to 8.8 and 6.07 to 6.90 g/L, respectively, after fermentation. Major organic acid in wines were identified as tartaric acid, malic acid, and citric acid. A small amount of free sugar such as sucrose and glucose were detected in wines, but fructose was completely absent. The soluble phenolic contents were decreased that ranges around 1.00 to 1.25 g/L, in contrast, browning degree were increased ranges around 0.212 to 0.412 after fermentation. The major flavor components were identified as ethyl acetate and hydrazine, and 1,1-dimethyl. Importantly, phenylethyl alcohol was detected from the all wines that have a typical rose like flavor. But sensory test results and preference of kiwi-persimmon (7:3) mixing wine was better than the other wines.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.348-356
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• 2008

For the effective use of rainbow trout, the seasoned and dried rainbow trout slice (SR) was prepared and its characterization was compared with the commercial skipjack tuna (CSS) and pork products (CSP) by determining chemical components and sensory evaluation. The moisture content of SR, 20.5%, was lower, and the lipid content of SR, 7.5%, was higher than those of commercial products, CSS and CSP. The protein content of SR (41.4%) was higher than that of CSS (28.6%), but lower than that of CSP (50.1%). The water activity of SR was 0.654, which was lower than those of CSS and CSP, 0.724 and 0.771, respectively. According to the results, the color of SR was lower in lightness and redness and higher in browning index and ${\Delta}$E value than that of commercial products. The texture of SR was harder than that of CSS, but softer than that of CSP. According to the result of taste value, the taste of SR was stronger than that of CSP, while weaker than that of CSS. The mineral (Ca, P, and Fe), total amino acid contents, and the n-3/n-6 of SR showed significant levels in nutrition and health functional senses.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.5
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• pp.594-600
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• 2009

Quality characteristics of white lotus leaf tea (LLT) fermented with or without mycelial Paecilomyces japonica were investigated. Extraction yield and browning index of hot water extract from non fermented and fermented LLTs were higher than those of ethanol extract (p<0.05). In all LLTs, nutritional components such as total free sugar, free amino acids and minerals of hot water extracts were higher than those of ethanol extracts except for total organic acids (p<0.05). Contents of total free sugar and organic acids were markedly increased through fermentation process of mycelial Paecilomyces japonica. in the same solvent extracts (p<0.05). Contents of most taste components of fermented LLT were increased by mycelial solid fermentation (p<0.05), but total free amino acids of two extracts were decreased in the range of $37.1{\sim}67.2%$ as compared to non-fermented LLT. Fifty-nine volatile compounds were identified by GC and GC-MS, including 11 aldehydes, 14 alcohols, 11 ketones, 11 hydrocarbones and 12 acids. Aldehyde and ketone compounds were more identified in fermented LLT than in non-fermented LLT being abundant alcohol compounds by simultaneous steam distillation and extraction. The most abundant compounds of LLT identified in this study were curcumene followed by 2,6-bis(1,1-dimethylethyl)-4-methyl-phenol and cyclohexen. Main compounds of fermented LLT were 2,6-bis(1,1-dimethylethyl)-4-methyl-phenol, butanoic acid, furfural, benzaldehyde, hexanoic acid and 2(3H)-furanone.

• Korean Journal of Food Science and Technology
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• v.48 no.2
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• pp.133-141
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• 2016

The physicochemical properties, antioxidant capacities, and sensory optimization of taro (Colocasia esculenta) under different aging conditions were investigated to develop black taro. Black taro was processed in three steps (steaming: $95{\pm}3^{\circ}C$ for 1 h; aging: 85, 90, $95^{\circ}C$ for 20, 40, and 60 h; drying: $60^{\circ}C$ for 24 h) and ground into a powder for all experiments. Black taro showed an increased crude fiber content and browning index compared to raw taro. Calcium oxalate contents, reducing sugar contents, moisture contents, and lightness values were decreased during the processing of taro. Improvements in total polyphenol content and antioxidant activity (DPPH, ABTS, FRAP) were observed in the black taro samples aged at higher temperature. Response surface methodology was used for sensory optimization, and the optimum aging conditions with the highest acceptance values were found to be $88.73^{\circ}C$ for 39.50 h for taste, and $88.82^{\circ}C$ for 42.60 h for overall acceptance.