• Journal of the Korean Society of Food Culture
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• v.19 no.5
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• pp.484-490
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• 2004

The present study was conducted to investigate extraction characteristics and antioxidative activity of Schiznadra chinensis extracts. Schiznadra chinensis was extracted by reflux extraction(RE) under different extraction conditions including solvent. The solid yield, turbidity, color value, titratable acidity, free sugar contents, electron donating ability(EDA) and superoxide dismutase(SOD)-like ability of Schiznadra chinensis extracts were determined. The highest solid yield value was obtained with water of 10 fold. No significant difference in turbidity and color value were found among the extracts prepared with various extraction solvents, 75% ethanol, 50% ethanol and water. The highest titratable acidity was obtained with water extracts of Schiznadra chinensis. The free sugar contents of Schiznadra chinensis extracted with water showed the highest value. Schiznadra chinensis extracts with water included higher contents of free sugar compared with those of the other solvent extracts,50% ethanol and 75% ethanol extracts. The total polyphenol compound content of Schiznadra chinensis extracted with 50% ethanol showed the highest value. Schiznadra chinensis extracts with 50% ethanol included higher contents of total polyphenol compound compared with those of the other solvent extracts, water and 75% ethanol extracts. The electron donating ability of extracts were 60.87% in water, 57.24% in 50% ethanol, and 55.61% in 75% ethanol.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.333-337
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• 2001

The effect of roasting of Omija (Schizandra chinensis Baillon) on the physicochemical properties and the sensory quality of the extract was investigated in order to improve the quality of Omija beverage. The response surface methodology was introduced to optimize the roasting condition of Omija based on the sensory quality of the extract. The titratable acidity, the soluble solid content and the reducing sugar content of the extract increased with a mild roasting, but decreased with an excessive roasting. Prolonged roasting at high temperature decomposed red pigment making the color of the extract lighter, less red and less yellow. A mild roasting of Omija improved the sensory quality of the extract, and the highest sensory quality of the extract was provided with the roasting at $180^{\circ}C$ for 10 min, indicating the optimum roasting condition of Omija. The extract of the roasted Omija was superior in sensory properties to that of the unroasted one.

• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.109-119
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• 1989

To improve the storage method of Kimchi, optimum ripening Kimchi for an irradiation treatment(the time of around 0.3% in total acidity of Kimchi) was irradiated by doses of 1, 2, 3 kGy with Co-60 ${\gamma}-radiation$ and stored at $10^{\circ}C$. Total aerobic bacteria increased in the beginning of storage and then decrease slowly as the number of total lactic acid bacteria increased. Total lactic acid bacteria initially loaded by $10^8\;cells/ml$ in Kimchi shortly after irradiation reduced to $10^4-10^6\;cells/ml$ with 1-3 kGy doses and decreased gradually through the whole storage period. The initial load of yeast, $10^3\;cells/ml$, increased steadily during Kimchi storage and led to more than $10^4\;cells/ml$ after 30 days of storage. While it maintained tha the load in 2-3 kGy irradiated groups after 30 days of storage was less than that at the beginning of storage. pH, acidity and volatile acid in the nonirradiated group were 4.0, 0.7% and 0.06%, respectively at the 15th day after storage, but at the 30th day after storage, 2-3 kGy irradiated groups showed different values, 4.1, 0.58-0.63%, and 0.04-0.05%, respectively. The texture(firmness) of Kimchi reduced along with storage time, and 2 kGy irradiated group proved most favourable in its texture during storage. In the sensory evaluation of Kimchi, nonirradiated group was inedible after 15 days of storage, whereas 2-3 kGy irradiated groups could proling the storage-life of Kimchi over 2 times compared with the nonirradiated Kimchi, showing the good sensory quality even after 30 days of storage.

• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.68-74
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• 1989

The changes of the contents of chemical components and sensory evaluation of Kimchis which were prepared by addition of different amounts of garlic were investigated during fermentation at $21^{\circ}C$ for 8 days. The range of salinity of Kimchis was 1.8-2.0% The titratable acidity of Kimchis was rapidly increased with garlic contents during fermentation. Ascorbic acid was decreased with fermentation but increased with more addition of garlic. Total sugar content was decreased until third day and the free sugar content decreased to 0.8-1.1g/100g at the 8th day fermentation. It was found that lactic acid and succinic acid were relatively high among the nonvolatile organic acids. The lactic acid content increased with the addition of garlic while succinic acid was not certain. During the whole fermentation, the result of sensory evaluation suggested that Kimchis contained more than 2g garlic were more palatable and desirable than eliminated garlic.

• Food Science and Preservation
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• v.19 no.2
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• pp.178-184
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• 2012

The physiochemical property, nutrient composition, and functionality of apple juice sterilized at a low temperature (LT, $70^{\circ}C$, 30 min) or a high temperature (HT, $100^{\circ}C$, 20 min) were analyzed. The pH of the apple juice that was sterilized at LT (pH 4.72) was higher than that of the apple juice that was sterilized at HT (pH 4.57), and the acidity of the apple juice that was sterilized at HT (8.90%) was higher than that of the other sample. The sugar content of the two apple juice samples was 15 $^{\circ}Brix$, and the apple juice samples had high potassium, malic acid, and glutamic acid contents. The total polyphenol contents of the apple juice samples that were sterilized at LT and HT were 27.39 mg/100 mL and 23.24 mg/100 mL, respectively. The apple juice that was sterilized at LT had a significantly stronger DPPH radical scavenging activity than the apple juice that was sterilized at HT ($p$ <0.01), and the apple juice that was sterilized at LT had a lower hydroxyl radical scavenging activity level than the other apple juice. Finally, the apple juice that was sterilized at LT showed significantly stronger activities that inhibit enzyme-related oxidation than the apple juice that was sterilized at HT ($p$ <0.05).

• The Korean Journal of Mycology
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• v.42 no.3
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• pp.225-230
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• 2014

Sclerotinia sclerotiorum, a plant pathogenic fungus, can cause serious yield and quality losses in the winter lettuce field. For biological control of S. sclerotiorum, soil-born microorganisms that inhibit the mycelia growth of S. sclerotiorum and Fusarium oxysporum were isolated from diseased soil. Among the isolates, bacterial isolate, GG95, which was identified as Bacillus subtilis according to the morphological, physiological characteristics and by 16S rRNA similarity, showed the highest level of inhibitory activity. The growth conditions for B. subtilis GG95 were optimized in TSB media (pH 7) by culturing at $28^{\circ}C$ for 24 hrs. Maltose or fructose and peptone were selected as the best carbon and nitrogen sources, respectively. Greenhouse experiment was performed to test effectiveness of B. subtilis GG95 in the control sclerotinia rot. Drench application ($1{\times}10^8cfu/mL$, 3 times) of the bacterial culture broth to lettuce showed an effectiveness value of 88%, suggesting that B. subtilis GG95 would be a promising biocontrol agent for control of sclerotinia rot.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.1
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• pp.101-108
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• 1989

In order to determine optimal conditions for the preparation of Japanese apricot wine, the changes in major components were experimented during ripening. A weight was $18.3{\pm}2.57\;g$ at June 22 or so. Moisture was reached $92.1{\pm}0.17\;%$ at that time. Respiration amounts were decreased by degrees during the ripening of Japanese apricot but came near climacteric maximum state about June 22. pH was decreased from $2.76{\pm}0.025$ to $2.51{\pm}0.081$, titratible acidity was increased from $1.15%{\pm}0.083%$ to $1.39{\pm}0.061%$. Fe was detected most of all and Zn, Mg, Cu and Ca were checked by the next order in mineral contents. And the rate of mineral contents was decreasing phenomenon slightly with ripening. Total sugar, about June 8, was higher than any other time with $1.74{\pm}0.090%$ and reducing sugar was increased with similarly a tendency of total sugar. Malic and citric acid were much of organic acids. The content of malic acid was decreased greatly but ctric acid was increased during ripening.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.3
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• pp.443-448
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• 2010

This study investigated alcohol fermentation conditions for preparation of tomato wine. The alcohol contents of tomato wines prepared from semi-mature and full-mature tomato were about 11% whereas that of immature tomato was slightly lower (10.6%). When characteristics of tomato alcohol fermentation were examined on pre-treatment conditions, the wine from full mature-crushed whole tomato contained lower alcohol at 10.6% than those of full mature-crushed tomato removed stem and full mature-tomato juice removed stem (about 11%). For the effect of initial sugar, the alcohol content and sugar content of tomato wine increased in proportion to the concentration of initial sugar (8.8~14.4% and $5.5{\sim}9.2^{\circ}Brix$). However, initial titratable acidity and pH did not affect the alcohol contents during fermentation, and suggesting needed to be supplementation for sensory improvement of tomato wine. When the quality characteristics of tomato wine fermented under these optimal conditions were investigated, alcohol content, sugar content, titratable acidity and pH were found to be 11.1%, $6.1^{\circ}Brix$, 0.68% and 3.7, respectively. For alcohol components, the total amounts of methanol and fusel oil were 346 ppm and 313 ppm. In addition, maltose showed the highest level of 264.6 mg% in the free sugar analysis of tomato wine whereas sucrose contained 18.7 mg%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1587-1594
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• 2009

This study investigated the physico-chemical and sensory quality of Doenjang added with red pepper (Capsicum annuum L.) seed. The initial moisture content and salt content of Doenjang were 52.03-53.79% and 13.28-14.05%, respectively. The moisture and salt contents of Doenjang slightly decreased and increased, respectively, as fermentation periods increased. According to increasing fermentation periods, pH of Doenjang showed a little decreasing value although there were no difference between samples with various red pepper seed contents. On the other hand, titratable acidity of Doenjang increased as fermentation periods increased. Also, Doenjang added with red pepper seed had higher titratable acidity value than control Doenjang without red pepper seed. In the color of Doenjang, ‘L’ of lightness, ‘b’ of yellowness, and ‘a’ of redness were decreased as fermentation periods increased. Also, generally, increase of red pepper seed concentration resulted in higher values of redness (a), yellowness (b) and lightness (L) of Doenjang. Also, amino-type nitrogen content, which was 497-623 mg% in initial fermentation period samples, increased to 1,000 mg% for control and to 756~896 for red pepper added at the fermentation 120 days. In the total microbes, total cell count in the Doenjang samples was in the range of $10^7{\sim}10^8$ CFU/g regardless of fermentation periods. In contrast, yeast and mold number of Doenjang samples showed the range of $10^5$ CFU/g at the initial fermentation periods and decreased thereafter. In the sensory evaluation of Doenjang, unique Doenjang flavor increased regardless added red pepper seed as fermentation periods increased.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.1
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• pp.80-87
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• 2016

This study was conducted to investigate the physicochemical properties and antioxidant activities of strawberries from different cultivars and ripening stages grown in Korea. Fragaria ananassa 'Seolhyang' and 'Janghee' in unripe and ripe stages were used in this study. Overall, firmness of unripe fruits was harder than that of ripe fruits, whereas firmness of 'Seolhyang' was harder than that of 'Janghee'. There was no significant difference in soluble solid content (SSC) between the two cultivars, whereas SSC increased when fruits matured. Total phenolic and flavonoid concentrations of 'Seolhyang' were greater than those of 'Janghee' cultivar. However, there was no ripening effect on total phenolic concentration in both cultivars. Total anthocyanin concentrations of the two cultivars were higher in ripe stage while that of 'Janghee' was greater than that of 'Seolhyang' statistically. Total antioxidant activities of 'Seolhyang' were greater than those of 'Janghee'. Total phenolic and flavonoid concentrations were highly correlated with antioxidant activities but there was no correlation between total anthocyanins and total antioxidant activities.