• Journal of the Korean Society of Tobacco Science
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• v.7 no.1
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• pp.49-55
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• 1985

low grade leaves of flue-cured (N.C. 2326) and air-cured (Br 21) have been heated at $140^{\circ}C$ for 10 and 20 minutes, respectively. As heating duration increased, each contents of nicotine, total nitrogen, total sugar and free amino acid decreased in both leaves. The result obtained from this experiment are as following 1. Nicotine content decreased in both leaves. Heating for 10 and 20 minutes showed respectively nicotine decrease of 13.2% and 21.6% for Br 21 and 8.2% and 13.2% for N.C.2326. Decrease of total nitrogen and total sugar was inversely proportional to the heating duration. N.C. 2326 in the decrease out numbered Br.21 by the ratio 2: 1 for 10min.-heating, and 5:4 for 20 min.-heating. 3. Total free amino acid was decrease by 17.1% and 13.85 for N.C. 2326 and Br 21, respectively when heated for 10 min., and 25.6% and 26.5% respectively when heated for 20 min. When sucrose was added to Br 21, th decrease ratio of total free amino acid of Br.21 was increased. It is suggested that the addition of sucrose could promote the browning reaction in Br 21 leaves.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.7-14
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• 2006

This study was carried out to examine the quality characteristics of soybean pastes made of Meju with mold-producing pretense isolated from traditional Meju. The changes in moisture content, enzyme activity (amylase, protease, lipase), reducing sugar, amino-type nitrogen contents and anti-oxidant activity were investigated during the aging period. The moisture contents decreased gradually with time. Amylase activity decreased during the aging period while pretense and lipase activities increased until 30-45 days of aging, but decreased thereafter, Especially pretense activity in soybean paste with mold was greater than that in the control. Amino-type nitrogen and ammoniacal nitrogen contents increased, but reducing sugar contents decreased with time. Amino-type nitrogen contents were greater in soybean paste made of Meju with isolated mold than those in the control. Antioxidative activity was also confirmed in soybean paste.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.2
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• pp.89-93
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• 2005

To manufacture the low-salt anchovy, Engraulis japonicus, sauces with $14\%$ and $17\%$ NaCl, anchovy sauce with $26\%$ NaCl was diluted with sterilized water and then heated at $60^{\circ}C$ for 10 min, 20 min, 30 min, and 40 min. The chemical and microbial changes of the heat-treated low-salt anchovy sauces stored at $25^{\circ}C$ were analyzed at different storage periods. Lactic acid and total nitrogen contents of $14\%$ and $17\%$ NaCl anchovy sauces decreased slightly during storage, but pH, VBN and amino nitrogen contents were almost constant. The amino nitrogen content of $17\%$ NaCl anchovy sauce was higher than that of $14\%$ NaCl anchovy sauce. Total viable cell and lactic acid bacteria were not detected in the anchovy sauce heated at $60^{\circ}C$ for more than 20 min and only proteolytic bacteria was determined less than 10 CFU/mL. The 17% NaCl anchovy sauce heated at $60^{\circ}C$ for 30 min was relatively good for the taste and odor by sensory evaluation.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.3
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• pp.395-400
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• 2009

This study was performed to examine the effects of salt addition levels on changes in the physicochemical properties of salted and fermented shrimp for HACCP determination. The salted shrimp were prepared from fresh shrimp using different concentrations (8, 18, 28%) of chunil salt, and were then fermented at $10^{\circ}C$ for 160 days. Amino nitrogen, VBN and TMA contents rapidly increased in the 8% group during the fermentation period, while the 18% and 28% groups maintained their initial levels throughout the 160 day fermentation period. The thiobabituric acid (TBA) values of the groups increased rapidly over 120 days of fermentation, and then decreased thereafter. The TBA values of the 18% and 28% groups were lower than that of the 8% group. The peroxide values of the 18 and 28% groups rapidly increased over 30 days of fermentation, whereas the values for the 8% group, rapidly increased with 60 days of fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1044-1049
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• 1997

Physicochemical characteristics of kochujangs prepared with the powders from 4 different red pepper varieties, were investigated during 90 days fermentation to obtain information for the industrial production of traditional kochujang. Water activities and consistencies of all varities slightly decreased during fermentation, but in consistency Jangter kochujang was higher than others. The red values in color of all sample remarkably increased after 15 days. Especially L, a and b values of Hongkwang kochujang were higher than those of others. The acidities of 4 kochujangs linearly increased during fermentation. Reducing sugar contents of kochujang increased until 30 days but thereafter decreased slightly, showing highest value for Hongkwang kochujang. Ethanol contents increased until 75 days and were higher in Kumtop and Jangter kochujang. Amino and ammonia nitrogen contents rapidly increased until 30 days. Ammonia nitrogen content was gradually decreased after 30 days. Amino nitrogen contents were higher in Hongkwang kochujang.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.12
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• pp.1748-1758
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• 2012

Two experiments were conducted to evaluate the effects of chemical composition of wheat shorts and red dog on energy and amino acid digestibility in growing pigs and to establish prediction models to estimate their digestible (DE) and metabolizable (ME) energy content and as well as their standardized ileal digestible (SID) amino acid content. For Exp. 1, sixteen diets were fed to thirty-two growing pigs according to a completely randomized design during three successive periods. The basal diet was based on corn and soybean meal while the other fifteen diets contained 28.8% wheat shorts (N = 7) or red dog (N = 8), added at the expense of corn and soybean meal. Over the three periods, each diet was fed to six pigs with each diet being fed to two pigs during each period. The apparent total tract digestibility (ATTD) of energy in wheat shorts and red dog averaged 75.1 and 87.9%. The DE values of wheat shorts and red dog averaged 13.8 MJ/kg (range 13.1 to 15.0 MJ/kg) and 15.1 MJ/kg (range 13.3 to 16.6 MJ/kg) of dry matter, respectively. For Exp. 2, twelve growing pigs were allotted to two $6{\times}6$ Latin Square Designs with six periods. Ten of the diets were formulated based on 60% wheat shorts or red dog and the remaining two diets were nitrogen-free diets based on cornstarch and sucrose. Chromic oxide (0.3%) was used as an indigestible marker in all diets. There were no differences (p>0.05) in SID values for the amino acids in wheat shorts and red dog except for lysine and methionine. Apparent ileal digestibility (AID) and SID values for lysine in different sources of wheat shorts or red dog, which averaged 78.1 and 87.8%, showed more variation than either methionine or tryptophan. A stepwise regression was performed to establish DE, ME and amino acid digestibility prediction models. Data indicated that fiber content and amino acid concentrations were good indicators to predict energy values and amino acid digestibility, respectively. The present study confirms the large variation in the energy content and amino acid digestibility in wheat shorts and red dog, and describes the factors that influence this variation and presents equations based on chemical composition that could probably be used to predict the DE and ME values as well as the amino acid digestibility of wheat shorts and red dog.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.5
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• pp.757-763
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• 2010

The qualities of Deodeok Doenjang including physicochemical characteristics and sensory properties were investigated over the following range of Deodeok levels: 5, 10, 15 and 20% (all w/w). The strains used in the manufacturing of Doenjang were Bacillus sp. B-3 and Aspergillus sp. M-9 with the highest enzyme activities like amylase and protease. In case of Deodeok Doenjangs prepared with Bacillus sp. B-3, the amino-type nitrogen of Doenjang containing 10% (w/w) Deodeok was produced more than others during fermentation for 40 days. Amino-type nitrogen produced in Deodeok Doenjang prepared with Aspergillus sp. M-9 was more than one of Deodeok Doenjangs with Bacillus sp. B-3 and a commercial Doenjang. When Deodeok content exceeded 15% (w/w), higher content resulted in lesser amino-type nitrogen production. The results showed that Deodeok had influenced growth of Bacillus sp. and Aspergillus sp. Sensory evaluation showed that Deodeok Doenjangs containing 10% (w/w) Deodeok and 1% (w/w) Bacillus sp. B-3 and containing 20% (w/w) Deodeok and 1% (w/w) Aspergillus sp. M-9 were superior to the other Doenjangs tested.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.3
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• pp.160-166
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• 2000

The reasonable level of nitrogen fertilizer of Gyokuro tea which is producted fresh leaves plucked from shade tea plants is a key factor to increase crop yield and quality. Nitrogen were applied at the level to 60, 80, 100 and $120kg\;10a^{-1}$. Analytical results of yield and quality of Gyokuro tea are summarized as follows : The soil fertility of experimental field was higher in organic matter($59.8g\;kg^{-1}$) and available phosphate($1,285mg\;kg^{-1}$), but lower in pH(4.79) compared to the common field. As the amount of nitrogen fertilizer application was increased to $80kg\;10a^{-1}$, the yield of tea leaves, the content of total nitrogen, total amino acid, caffeine and chlorophyll were increased. However, the yield of tea leaves was not increased above $100kg\;10a^{-1}$ and the increased level of nitrogen fertilizer did not show any different in the content of tannin and vitamin C. When the amount of nitrogen fertilizer application was raised, the content of thiamine and arginine increased, but the content of aspartic acid, serine and glutamic acid decreased. The content of fatty acid was produced $2.850{\sim}3.012mg\;100g^{-1}$ Especially, the content of oleic acid, linoleic acid and linolenic acid was higher at the level of $80kg\;10a^{-1}$ application than other treatments. As nitrogen was applied at $80kg\;10a^{-1}$, sensory score was 0.2~4.6 point higher than other treatments. Consequently, $80kg\;10a^{-1}$ is considered to be the best level of nitrogen fertilizer both quality and crop yield.

• Food Science and Preservation
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• v.24 no.6
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• pp.771-777
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• 2017

Although Doenjang is a representative traditional fermented food in Korea, made mainly from soybeans, it has been classified into a food group identified as having high sodium in the National Health and Nutrition Examination. It is necessary to develop a low sodium Doenjang to prevent the excessive sodium intake which may cause various diseases. However, the development of Doenjang with low sodium, without significant changes on quality, is an ongoing challenge. Therefore, the experiment was designed to reduce the salt content of the soaking water to 12.5-45%. The pH, saltiness. moisture, sodium, color, amino-type nitrogen, free amino acids and constituent amino acids composition of Doenjang were investigated to determine the effect of this salt reduction on the sensory quality of Doenjang. The reduction of sodium did not affect the pH, moisture and saltiness, and this changed maintained the same range as the control. The sodium content was reduced proportionally, and the amino acid nitrogen level was 500 mg%. Therefore, this study considered that a reduction of 25% of salt in the soaking water does not affect the quality of the Doenjang while reducing the sodium content of the final Doenjang.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.213-217
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• 2004

We evaluated the possibility of rapid fermentation of anchovy sauce using a commercial protease. The fermentation characteristics were monitored by response surface analysis. The content of total nitrogen was high (around 1 %) with fermentation at 51.7～57.5$^{\circ}C$ after 10.2～16.4 hours, but rapidly decreased at higher temperatures (6$0^{\circ}C$ or over), while the $R^2$ of polynomial equation was 0.9185 (p<0.05). The amino acid content rapidly decreased to approximately 600 mg% and less at high temperature (6$0^{\circ}C$ and over), and the $R^2$ was 0.9578 (p<0.01). The free amino acids were affected more by fermentation time when fermentation temperature was lower, and the $R^2$ for total free amino acids was 0.8496 (p<0.10). The $R^2$ for sweet free amino acids was 0.9144 (p<0.05). According to the results of this study, the optimal conditions for anchovy sauce fermentation were predicted to be 52.5～56.9$^{\circ}C$ and 13.3～16.4 hours, and the predicted values and actual values of each response variable were similar to each other when the fermentation was performed at a random point within the optimal range. Also, the comparison of the quality between the quick anchovy sauce and sauces currently on the market showed that the content of sweet amino acids was higher in the former than in the latter.