• Korean Journal of Soil Science and Fertilizer
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• v.38 no.1
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• pp.38-44
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• 2005

In addition to the variation in nitrate accumulation of vegetables due to environmental conditions, there is also a distinct genetic variation. The variation of nitrate accumulation in some cultivars of lettuce and spinach commonly cultivated in Korea was investigated. Ten cultivars for both lettuce and spinach were grown in plastic containers filled with a 1:1 mixture of perlite and vermiculite with application of Hoagland No. 2 nutrient solution of high nitrate content (17.3 mM N) in a greenhouse condition. Plants were harvested four weeks after transplanting four-leaf stage seedlings. Plant growth was measured by fresh and dry matter of shoot, and contents of nitrate and other inorganic ions and organic solutes including sugar, amino acids and organic acids were measured. Large and significant genotypical variations in the nitrate content of the plants were found for both lettuce and spinach, and high negative correlations between nitrate content and fresh or dry weight were found in lettuce and spinach. Variation in nitrate accumulation of lettuce and spinach cultivars was not directly related to the differences in contents of organic and inorganic solutes, and this result indicates that photosynthesis and osmotic regulation are not directly related with the nitrate accumulation. Considering the correlations between nitrate content and plant growth of this study, it can be simply suggested that different cultivars of lettuce and spinach have their own inherited growth and physiological characteristics and also optimum nitrogen level required for the growth. Therefore when available nitrogen in root media is higher than the optimum level required for the inherited growth potential, some of the excess nitrate supplied can be accumulated in plants.

• Applied Biological Chemistry
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• v.14 no.2
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• pp.121-129
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• 1971

During the Brewing of Soy Sauce on an industrial scale, Saccharomyces rouxii $T_9$ was cultured and added to the soy sauce mash. The comparative experiments of soy sauce mash in non-addition and addition group of yeast were examined in this report. The yeast flora and chemical composition of Soy sauce mash through out the brewing were observed and the results obtained were as follows. (1) The number of Osmophilic yeast in one ml of soy sauce mash showed $185{\times}10^3$ 1 month after mashing and $750{\times}10^3$ 4 months after mashing in case of yeast group, while presented as $98{\times}10^3$ 1 month after mashing and $394{\times}10^3$ 4 months after mashing in case of non-yeast group. And the number of Osmphilic yeast in yeast group was twice of that in non-yeast group. (2) The number of ordinary yeast of TTC red group was shown as $2132{\times}10^3\;to\;3252 ×10^3$ 5 to 6 months after mashing in case of yeast group, while presented $752{\times}10^3\;to\;1251{\times}10^3$ in case of non-yeast group. And the yeast group was shown more than non-yeast group in ordinary, red pink and pink yeast number. (3) TTC red yeast were strongly appeared in both addition and non-addition group of yeast from 1 month after mashing to 6 months after mashing. (4) Though total nitrogen, pure extract, pH and buffer action contents of soy sauce showed similiar tendency in yeast and non-yeast group, alcohol and color density contents were highly appeared in yeast group and reducing sugar content was in non-yeast group respectively. (5) By the results of Organic function test of soy sauce mash, the difference of taste quality in yeast and non-yeast group were not evidently appeared, however, the appearance and flavour of the soy sauce were better in yeast group than in non-yeast group.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.72-78
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• 1997

The levels of reducing sugars, organic acids and fatty acids, known as precursors of major flavors induced from dried sellfish, were analyzed to investigate their behaviors during drying process. Free reducing sugar contents were markedly decreased in all samples by boiling, Its content in Blue mussel and Short-necked calm samples significantly decreased after drying process. Among the eight different organic acids from blue mussel, Short-necked calm and Pacific oyster samples, succinic acid in blue mussel and short-necked calm samples was measured with $74.9\%\;and\;67.4\%$, respectively. In the sample of Pacific oyster, succinic acid content was found to be $38.4\%$, but pyroglutamic acid content was the highest level with $41.6\%$. Contents of organic acids with exception succinic acid were significantly reduced in all three samples of sun-dried or hot-air dried. The content of succinic acid in the samples of sun-dried and hot-air dried pacific oyster reduced to $53.0\%\;and\;44.2\%$, respectively, but relatively small decrease $(29.0\%\;and\;10.0\%)$ was observed in sun-dried and hot-air dried short-necked calm samples, respectively. Content of polar lipid with the major fatty acids profile of C16:0, C16:1, C20:5 and C22:6 was consisted of $59.1\%,\;66.7\%\;and\;42.4\%$, respectively, in blue mussel, short-necked calm and pacific oyster samples and the content of polyene fatty acids was appeared to be $40.5\%,\;48.6\%\;and\;48.9\%$, respectively. Relatively high peroxide value in all boiled-dried products samples was found to be $41.64\~86.80\;meq/kg$ sample. Carbonyl value in boiled-dried products samples was found to be $15.55\~27.99\;meq/kg$, but its value in broiled products samples was significantly high level of $127.6\~136.5\;meq/kg$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.24-32
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• 1984

In order to process instant foods which hold appropriate moisture contents and soft texture, four kinds of retort pouched seasoned-oyster products were prepared as control, seasoned products, solid smoked and liquid smoked product after seasoning and their processing conditions and quality stability during 100 days of storage were investigated. The optimum processing conditions of retort pouched seasoned-oyster product were as follows ; namely, raw oyster was seasoned at $105^{\circ}C$ for 10 min with seasoning solution prepared from sugar, sorbitol, salt, monosodium glutamate and 5'-ribonucleotide and then dipped for 30 seconds in Smoke-EZ solution(Alpha Foods Co., Ltd.) after predried for 30 min in hot-air drier. After. smoking, the seasoned and liquid smoked oyster was dried at $40-42^{\circ}C$ for 2.5 hours, vacuum packed in plastic film bag, and sterilized in a hot water circulating retort at $120^{\circ}C$ for 16 min. Comparing their quality before and after sterilization, TBA value of all the products after sterilization slightly decreased and among texture profiles hardness, toughness and chewiness slightly decreased, while elasticity and cohesiveness were rarely changed. Color value (a value) of the product treated with solid smoke or liquid smoke increased after sterilization. During storage pH, VBM and water activity of all products changed little and TBA values of the solid smoked product and liquid smoked one were lower than that of the others. Viable cell count was negative and texture changed little during storage. As for color difference during storage, green meat appeared on the surface of control and seasoned product after 15 days storage, while the masking of green meat could achieved by solid and liquid smoking treatment. And liquid smelling treatment was more effective than solid smoking. As a conclusion, retort pouched seasoned-oyster product treated with liquid smoke kept their good quality during 100 days storage and it seemed to be consumed as one of the instant foods which hold appropriate moisture contents and soft texture.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.962-968
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• 2011

The objective of this study was to investigate the chemical components and quality characteristics of three waxy corn varieties (Heukjinju, Ilmi, and Yeonnong1) harvested by conventional cultivation (CC) and environmentally-friendly cultivation (EFC). Crude ash content of the three corn varieties was higher, but not significant, in CC than EFC. Crude fat and protein contents in Heukjinju were higher in EFC, and amylose content was significantly higher (p<0.001). Free sugar, minerals, and fatty acid composition patterns varied according to the cultivation method. Vitamin E contents in the Heukjinju and Yeonnong1 cultivars were higher in CC than EFC. Total polyphenol content of waxy corns on EFC and CC were 175.28 and 204.00 mg/100 g, respectively, in the Heukjinju cultivar (p<0.01), and 148.64 and 158.42 mg/100 g, respectively, in the Ilimi cultivar, and 123.24 and 128.30 mg/100 g, respectively, in the Yeonnong1 cultivar. 2,2-Diphenyl-1-picrylhydrazyl radical scavenging activity on EFC and CC was 1.51 and 1.76 in Heukjinju cultivar (p<0.05), 0.29 and 0.34 in Ilmi cultivar (p>0.05), and 0.39 and 0.42 mg trolox eq/g in Yeonnong1 cultivar (p>0.05), respectively. However, 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate) radical scavenging activity was higher in CC than EFC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.100-108
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• 2016

This study investigated the quality characteristics of factory-style ssamjang (FSS) and commercial handmade-style ssamjang (HSS) products. Moisture, crude protein, and crude fat contents were significantly higher in the HSS groups (49.37~62.12%, 9.39~13.46%, and 4.40~8.35%) than the FSS groups (41.94~45.83%, 7.50~9.09%, and 1.81~3.36%). Salt content was higher in the HSS groups (6.33~11.18%) than the FSS groups (6.10~7.57%). Moreover, the average salt content (7.51%) of the HSS groups and the FSS groups was lower than that of commercial ssamjang (8.73%). Hunter's color value was also significantly higher in the FSS groups. However, free sugar, organic acid, and free amino acids contents varied greatly between the FSS groups and the HSS groups, which was likely due to the different manufacturing method, ripening degree of doenjang and the main material used for ssamjang.

• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.237-245
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• 2004

The physicochemical and physiological activities of domestic garlic from 3 different areas (Namhae, Jeju and Uiseong) were analyzed. The contents of moisture, ash, crude protein and crude fiber in garlic were little different in 3 kinds of area. Total sugar and water soluble phenolic compounds were higher in garlic from Namhae. The free sugars found in garlic were fructose, sucrose and lactose. Five kinds of organic acids were determined. Malonic acid and citric acid contents in garlic from Namhae were 23.7${\pm}$1.16 mg% and 22.1${\pm}$0.82 mg%, respectively. Total mineral content of garlic samples were in a range of 7112.6～9067.3 mg%, the potassium content showed the highest concentration (4117.3${\pm}$7.19～5175.3${\pm}$9.61 mg%). The electron donating abilities in 0.2% of garlic from Namhae and Uiseong showed 46.2${\pm}$1.25% and 37.0${\pm}$1.l6%, respectively. The nitrite scavenging effect was measured at different conditions (pH 1.2 and 4.2). The nitrite scavenging effects were higher at pH 1.2, and reached more than 95% by adding 0.2% and 0.1 % of garlic juice at pH 1.2. Addition 0.02～0.001 % garlic juice in showed the SOD-like activities. Its activity of garlic from Namhae. was a range of 6.0${\pm}$0.37～14.4～0.69%. It was found that 0.2% and 0.1% garlic showed strong antimicrobial action against growth of all the tested bacteria. Antimicrobial action. was showed 74.7${\pm}$0.70% and 51.7${\pm}$1.l1% on Sal. typhimurium in 0.2% of garlic from Namhae and Uiseong and 28.6${\pm}$0.90% on B. subtilis in garlic from Jeju.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.342-347
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• 2006

Korean pear juice heat-treated at various temperatures (110, 120, 130, 140, and $150^{\circ}C$) and times (1, 2, 3, 4, and 5 hr) was analyzed to determine total polyphenol, total flavonoid, free sugar, and 5-HMF contents, and DPPH free radical-scavenging activity. Total polyphenol, total flavonoid, and 5-HMF contents, and antioxidant activities increased, whereas fructose content decreased with increasing heat treatment temperature and time ($p\;{\pm}\;0.007\;mg/g$ with treatment at $150^{\circ}C$ for 1 hr (unheated pear juice: $0.233\;{\pm}\;0.024\;mg/g$). Highest total flavonoid content was $561.49\;{\pm}\;16.93\;{\mu}g/g$ with treatment at $150^{\circ}C$ for 4 hr (unheated pear juice: $1.50\;{\pm}\;0.20\;{\mu}g/g$). $IC_{50}$ value was highest, $1.93\;{\pm}\;0.01\;mg/g$, at $150^{\circ}C$ for 2 hr, whereas that of unheated pear juice was $64.58\;{\pm}\;0.99\;mg/g$. Glucose content was not affected by treatment conditions, whereas fructose content decreased with treatment at $140^{\circ}C$ for 3 hr. Highest 5-HMF content was $5,594.93\;{\pm}\;6.43\;ppm$ at $150^{\circ}C$ for 5 hr (unheated pear juice: $2.04\;{\pm}\;0.21\;ppm$). Correlation coefficients were observed among total phenolic, total flavonoid, and antioxidant activities, and between fructose and 5-HMF at significance level (p<0.001).

• Horticultural Science & Technology
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• v.31 no.2
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• pp.194-202
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• 2013

The aim of this work was to study the changes in fruit quality and antioxidant activity depending on ripening levels, storage temperature and storage periods in two strawberry cultivars (Fragaria ${\times}$ ananassa cvs. Daewang and Seolhyang). Fully ripe strawberry fruits (100% colored fruits) and unripe strawberry fruits (50% colored fruits) were harvested and then stored at $4^{\circ}C$ and $15^{\circ}C$ for 10 days, respectively. Hardness, phytochemicals, sugars, organic acids and antioxidant activity of strawberry fruits were measured after storage for 5 and 10 days, respectively. When fruit hardness was compared between the two cultivars, 'Daewang' showed a greater degree of fruit hardness than 'Seolhyang'. 'Daewang' also showed higher amounts of phenolic compounds and sucrose than 'Seolhyang'. In contrary to this, 'Daewang' was shown to contain lower amounts of anthocyanin and fructose than 'Seolhyang'. However, antioxidant activities of both cultivars were almost identical. When the effects of storage temperature were examined on fruit hardness, fruits stored at $4^{\circ}C$ showed a higher degree of hardness than those stored at $15^{\circ}C$. During the period of fruit storage at $4^{\circ}C$ or $15^{\circ}C$, both cultivars showed marked decline in the contents of phenolic compounds as well as sucrose. Contrastingly, they showed higher amounts of anthocyanin and glucose after 10 days of storage. On the other hand, the contents of organic acids in strawberry fruits were influenced only by the period of storage, not depending on cultivars or temperatures. Antioxidant activities of fully ripe fruits declined remarkably after 10 days of storage, as compared to unripe fruits which showed a minor decrease or increase. When fully ripe fruits of both cultivars were stored at different temperatures, those stored at $15^{\circ}C$ showed a significant decrease in the antioxidant activity as compared to those stored at $4^{\circ}C$. However, changes of antioxidant activity in unripe fruits were minor. These observations in order to supply high quality strawberry suggest that fully ripe strawberry fruits should be harvested for the short-term storage and the appropriate ripe level fruit should be harvested for the long-term storage. Storage temperature is appropriate at $4^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.52-59
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• 1986

As one of trials to process instant sardine foods which can be preserved at room temperature, three kinds of products were prepared as seasoned-dried product (control, C), liquid smoked seasoned-dried product(S) and antioxidant treated seasoned-dried product(E), and their processing conditions and quality stability during storage were examined. Raw sardines were dressed, steamed and then filleted. The sardine fillets were seasoned with the mixed seasoning solution containing $28.0\%$ of sorbitol, $14.0%$ of sugar, $5.6\%$ of table salt, $1.8\%$ of monosodium glutamate, $0.6\%$ of garlic powder and $50.0\%$ of water at $5^{\circ}C$ for 15 hours, and dipped for 45 seconds in $10\%$ Smoke-EZ solution. After liquid smoking, the seasoned and liquid smoked sardine fillets were dried at $45^{\circ}C$ for 4 hours, vacuum packed in laminated plastic film bag(polyester/casted polypropylene= $12{\mu}m/70{\mu}m,\;15{\times}16cm$), and finally pasteurized in water at $95^{\circ}C$ for 30 minutes. The results obtained from chemical and microbial experiments during storage are as follows : the moisture contents, water activity and pH of the products showed little change, and VBN of them slightly increased during storage. The TBA value and POV of the products (E, S) were lower than those of control product(C) considerably. In color values, L value (linghtness) decreased while a and b value (red and yellow) revealed a tendency to increase during storage. The fatty acid composition of the products were similar to those of raw sardine, the predominant fatty acids were 16:0, 20:5, 18:1 and 22:6. The products (E, S) have a good preservative effect on highly unsturated fatty acids during storage. Viable cell counts of those products were negative and histamine contents were less than 2.0 mg/100 g. Among the texture profiles, hardness, elasticity and cohesiveness of the products slightly decreased during storage. Judging from the sensory evaluations, liquid smoked seasoned-dried product(S) was the most desirable, and the products could be preserved in good condition for 40 days at $25{\pm}3^{\circ}C$.