• Journal of Life Science
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• v.27 no.9
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• pp.1011-1019
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• 2017

This study examined the influence of sea wind mugwort extract treatment on quality characteristics of mackerel during storage. Mackerel were packaged individually and then immersed in 5% sea wind mugwort extract for 2, 3, or 4 hr and stored at $-20^{\circ}C$. The salinity of a control (no treatment) and that of mackerel immersed in sea wind mugwort for 2 hr was lowest (0.07%). pH of 5.90-6.23, and the change in acidity was in the opposite range. Immersion for 2, 3, and 4 hr led to a decrease in the tensile strength of the samples following storage, whereas the tensile strength of the control increased. The volatile basic nitrogen (VBN) content of the mackerel immersed for 2 hr was significantly lower than that of the control (5.6-15.4 mg% vs. 4.2-50.7 mg%). In the mackerel immersed for 2 hr, the total polyphenol and total flavonoid content was 286.3-497.0 mg gallic acid equivalents (GAE)/100 g and 177.5-385.6 mg quercetin equivalents (QE)/100 g, respectively. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis(3-ethyl-benzothizoline-6-sulfonic acid) (ABTS) radical scavenging activities of the mackerel immersed in sea wind mugwort for 2 hr were 50.6% and 61.3%, respectively. Overall, the immersion of mackerel in sea wind mugwort for a short time significantly improved quality characteristics, such as salinity, pH, acidity, hardness, antioxidant activity, and perceptible quality, following storage.

• KSBB Journal
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• v.27 no.1
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• pp.21-27
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• 2012

Five yeast strains were isolated from traditional Makgeollies, Makgeollies were made by isolated yeasts after cultivation, and then property changes of Makgeollies were analyzed according to yeasts, storage temperatures and storage periods. Average pHs were shown to be 3.22~3.88 and statistically changed according to yeasts used, storage temperatures and storage periods. Total acidities were statistically changed according to storage periods. Amino-type nitrogen contents were in the ranges of 0.009~0.245% and statistically changed according to storage temperatures especially at 18 and $25^{\circ}C$ for 15 days. Average alcohol concentrations were in the ranges of 7.5~18.5% and reduced until 10 days and increased for 15 days according to yeasts used and storage periods. Consequently, Makgeollies, made by isolated yeast strains originated from traditional Makgeollies, revealed that alcohol concentrations and amino-type nitrogen contents were changed but pHs and total acidities were not dramatically changed according to yeasts used. It suggests that development of various Makgeollies would be possible using isolated yeast strains in this study, and optimal storage condition of ready-made Makgeollies to maintain its original property turned out to be at $4^{\circ}C$ for 5 days. Especially, Makgeolli made by F strain showed the best quality on its property, therefore Makgeolli which maintains its property stably until 10 days when stored at $4^{\circ}C$ could be made using this strain.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.8
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• pp.1157-1163
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• 2014

This study was conducted to observe the effects of gas composition in modified atmosphere packaging (MAP) on the shelf-life of Longissimus dorsi of Korean Native Black Pigs-Duroc Crossbred ($KNP{\times}D$) during refrigerated storage. Muscle sample was obtained from the left side of carcass of seven months old of $KNP{\times}D$ barrow. The sample was sliced into 1 cm in thickness, placed on trays (two slices/tray) and filled with different gas composition, i.e. 0:20:80/$O_2:CO_2:N_2$ (MAP1), 30:20:50/$O_2:CO_2:N_2$ (MAP2) and 70:20:10/$O_2:CO_2:N_2$ (MAP3). Other slices of sample were vacuum packed (VP) as a control. All packs were stored at $5{\pm}1^{\circ}C$. At 12 d of storage, pH value of MAP2 and MAP3 were higher (p<0.05) than that of MAP1 and pH value of MAP1 was higher (p<0.05) than that of VP. At 6 d of storage, redness ($a^*$) value of MAP2 and MAP3 were higher (p<0.05) than that of VP and MAP1 and, at 9 and 12 d of storage, redness value of MAP3 was higher (p<0.05) than that of VP, MAP1, and MAP2. At 3, 6, 9, and 12 d of storage, the 2- thiobarbituric acid reactive substances (TBARS) value of MAP3 was higher than that of MAP2 and TBARS value of MAP2 was higher than that of VP and MAP1. At 3, 6, 9, and 12 d of storage, volatile basic nitrogen values of MAP2 and MAP3 were higher (p<0.05) than those of VP and MAP1. At 3 d of storage, total aerobic plate counts of MAP2 and MAP3 were higher (p<0.05) than those of VP and MAP1 and, at 6 d of storage, total aerobic plate counts of MAP3 was higher (p<0.05) than that of MAP1 and MAP2. However, there was no significant different total aerobic plate count among MAP1, MAP2, and MAP3 at 9 and 12 d of storage. There was no significant different total anaerobic plate count among MAP1, MAP2, and MAP3 during storage. It is concluded that the MAP containing 30:20:50/$O_2:CO_2:N_2$ gas composition (MAP2) might be ideal for better meat quality for $KNP{\times}D$ meat.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.6
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• pp.735-739
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• 2019

The purpose of this study was to measure pH, trimethylamine (TMA), and total volatile basic nitrogen (TVB-N) as indicators of freshness during largehead hairtail Trichiurus lepturus storage, and to compare these indicators with those obtained by the sensory evaluation of quality index method (QIM) sensory evaluation. Largehead hairtail samples were stored at 4℃ and evaluated every 3 days until decay. The QIM sensory evaluation indicated scores of 0, 8.9, and 20 on storage days 0, 6, and 20, respectively. By day 15, the samples were completely decayed. The pH slowly increased during the storage period, reaching a maximum of 7.4. In the day 6, TMA and TVB-N contents were 2.97 and 15.57 mg/100 g, respectively. Thus, at 4℃, the largehead hairtail starts to decay after 6 days and, after 9 days, cannot be consumed safely

• Journal of the Korean Society of Tobacco Science
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• v.29 no.2
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• pp.59-65
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• 2007

The study was carried out to investigate water activity, physicochemical properties and color degree of burley tobacco stored in shelf with different moisture content for 56 days. The study was consist of two experimental designs, that is, moisture content in burley tobacco was kept to 13 to 15 %, 17 to 19 %, and 21 to 23 % under ambient temperature of $20^{\circ}C$ with relative humidity of 24 %, and another group of in burley tobacco was only kept in ambient temperature of $3^{\circ}C$ with relative humidity of 50 % for 56 days with same water content of former treatment. Normal leaves were kept for 56 days under 21 to 23% of moisture content with increased water activity and TSNA(tobacco-specific nitrosamine content. It was considered that favorable leaves conditions are due to favorable microbial growth resulting in increased TSNA content. The total nitrogen content has not changed in two experimental groups for 56 days, otherwise the nitrate form nitrogen and total alkaloid contents were only increased by 21 to 23 % of water content. Degree of pH change was slightly decreased in both storage and water treatment. It was more decreased in 21 to 23% of moisture content than that of other moisture content. In stored leaf tobacco, higher moisture content caused lower brightness, yellow degree, and carbonization quotient.

• Journal of Applied Biological Chemistry
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• v.57 no.4
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• pp.287-294
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• 2014

To improve the shelf life of low-salt Kochujang, Korean hot pepper paste, antimicrobial materials were added at different times before and after aging. The kochujang was then packaged and stored at $30^{\circ}C$ for 15 weeks, and changes in microbiological and physiochemical properties were evaluated. Hunter a- and b-values decreased considerably during storage. The total color difference (${\delta}E$) was greater in the ethanol-chitosan (EC) treatment than in the control and after pasteurization (A-P) treatment. Gas was produced until the seventh week of storage. The control and the A-P treatments produced more gas than the other treatments, and these had the largest number of yeasts and aerobic bacteria. The pH of the EC treatment was higher than that of the other treatments, and the A-P treatment had the highest level of titratable acidity. During storage, the oxidation-reduction potential was lower in the EC and ethanol-mustard-chitosan (EMC) treatments. The reducing sugar content decreased remarkably in the control and A-P treatments, with high production of ethanol. There was a significant change in the content of amino-type nitrogen in the control and A-P treatments, and the content of ammonia-type nitrogen was lowest in the EMC treatment. In the sensory test of kochujang, the ethanol-mustard (EM) and ethanol (E) treatments were significantly higher than the EC, control, and A-P treatments (p <0.05). EM or E alone was effective in extending the shelf life of kochujang when added before aging.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.403-408
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• 1999

This study was conducted to investigate chemical properties, quality stability and utilization of approved sardine surimi(ASS) which is developed our laboratory. The product yield of the ASS was about 3 times higher than that of usual sardine surimi(SS). The proper addition concentration of sodium bicarbonate was 0.1% for the neutralization of the ASS. The content of salt soluble protein nitrogen in the ASS was about the half of that in the SS, while the content of water soluble protein nitrogen was 2.4 times higher in ASS. The total amount of free amino acids in the ASS was about 11 times higher than that of the SS. Predominant free amino acids in the ASS were histidine, taurine, glutamic acid and alanine, and those four amino acids occupied 94% of total amount of free amino acids. During cold storage at 21oC for 6 months, the quality of ASS was more stable than that of SS in judging from changes of water soluble and salt soluble protein nitrogen, AV and POV. Quality of fish burger, fish sausage and fried fish paste processed in accordance with commercial processing preparation using the ASS or SS exclusively and mixtures which other white meat fish surimi(alaska pollack, hair tail and sole) were proportionallly added to each of two types of sardine meat were evaluated. In case of fish burger, the product processed from the ASS only were superior.

• Journal of Plant Biology
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• v.30 no.2
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• pp.95-108
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• 1987

Effects of allopurinol (2mM), a specific inhibitor of xanthine oxidase, on the growth and metabolism of llantoin in dark grown Chinese cabbage (Brassica campestris L.) seedlings were investigated. Allopurinol treatment maintained the fresh and dry weights of cotyledons at higher levels, but inhibited the elongation of hypocotyls and roots of the seedlings. Total nitrogen content in the cotyledons decreased at slower rate by allopurinol. Accordingly, the levels of total nitrogen contents in the hypocotyls and roots, were depressed by the inhibitor. In the cotyledons, allopurinol began to elevate RNA levels after day 3, which it did not affect DNA level throughout the experiment. Activities of xanthine oxidase (XO:EC 1.2.3.2), uricase (UO:EC 1.7.3.3) and allantoinase (AL:EC 3.5.2.5) in the cotyledons were examined. The activity of XO was not detected, but the accumulation of xanthine by allopurinol treatment presented an indirect evidence of the existence of XO in the organ. Allopurinol kept UO activity high up to day 2 after sowing and depressed AL activity throughout the experiment. By allopurinol treatment, allantoin content was kept high over the control both in cotyledons and roots, but it was kept low in hypocotyls. The level of allantoic acid in the 3 organs were shown to be depressed by allopurinol. These results suggest that allantoin and allantoic acid produced by the degradation of stored and newly synthesized RNA are transported from the storage tissue to hypocotyls and roots as important nitrogen sources for the development of Chinese cabbage seedlings.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.3
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• pp.107-112
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• 2018

In this study, we conducted to analyze and quantify the amount of nitrogen supply into the rice paddies from the rainfall during cropping and non-crop periods. Rainfall monitoring conducted 85 times from June 2015 to December 2017. Nitrogen supply of cropping season ranged from 5.37 to 7.70 kg/ha, while non-cropping season were supplied from 3.97 to 4.42 kg/ha. The supply of T-N in the crop period was more than 60% of the total supply. And as a result of analyzing the correlation between the characteristics of rainfall and the supply amount, nitrogen concentrations in rainfall were decreased with increasing rainfall, but the supply amount was increased. Therefore, efforts should be made to increase the rainfall utilization and to increase the nitrogen supply of crops by increasing rainfall storage through drainage management.

• Korean journal of food and cookery science
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• v.19 no.1
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• pp.72-78
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• 2003

This study was conducted to investigate the physicochemical and organoleptic characteristics and freshness of wild and cultivated Paralichthys olivaceus during storage. By the results of morphological observation, wild Paralichthys olivaceus had white abdomen, light black skin and transparent muscle, but cultivated Paralichthys olivaceus had black spotted abdomen, dark black skin and dark pink muscle. Moisture contents of wild and cultivated Paralichthys olivaceus were similar, but the lipid content was higher in cultivated Paralichthys olivaceus than that of wild Paralichthys olivaceus. Sensory scores of appearance, taste, texture and overall acceptability were higher in wild Paralichthys olivaceus than that of cultivated Paralichthys olivaceus. The reason was that lipid content was higher in cultivated Paralichthys olivaceus The freshness of cultivated Paralichthys olivaceus seemed to last shorter than that of wild one due to rapid increase of the volatile basic nitrogen content, pH and total microbial count during storage.