• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.79-84
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• 2002

Changes of microbiological and physicochemical characteristics of gamma irradiated Doenjang with low salt were studied. Samples were prepared by mixing the Doenjang and the Chungkukjang with 6% and 8% of salinity. The mixture was irradiated by gamma-ray with dose of 0, 5, 10, 20 kGy, and each sample was stored at $25^{\circ}C$ for 8 weeks. The results showed that the Bacillus cell was inactivated by $10^4-10^5\;cells/g$ with dose of 10 kGy, and yeast and Lactobacillus group were nearly eliminated by 10 kGy. The general quality of gamma irradiated low salt Doenjang, such as amino nitrogen, protease activity, and pH, were more stable than that of control during storage periods. The sensory evaluations showed that 8% (salt)-5 kGy and 6% (salt)-10 kGy irradiated samples were more acceptable than market purchased Doenjang. Therefore, it was considered that gamma irradiation was effective for maintaining better quality of low salt Doenjang and suitable radiation dose was 5 kGy in 8% salted, and 10 kGy in 6% salted sample.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1279-1284
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• 2016

To obtain enzyme hydrolyzed vegetable protein (EHVP) with a salty and umami taste, defatted soybean meal was treated with proteases such as Flavourzyme$^{(R)}$ (F), Neutrase$^{(R)}$ (N), Alcalase$^{(R)}$ (A), and Protamex$^{(R)}$ (P) in various reaction orders. The highest soluble solid content of EHVP was 5.60% in enzyme reaction order NAFP although there was no significant difference. Amino type nitrogen was highest in ANFP (102.76 mg%) and APNF (102.85 mg%). In the sensory descriptive analysis, salty taste was highest in PNFA (11.81), followed by NPAF (10.14), FPNA (10.00), APNF (9.80), NAFP (9.76), AFNP (9.57), APFN (9.52), and NPFA (9.50) with no significant difference among treatment. Umami taste was not significantly different among the various enzyme treatments. Bitter aftertaste was highest in AFPN (5.67) and lowest in FAPN (2.38), PNAF (2.62), and NAPF (2.48). In the principle component analysis, EHVPs of PNFA, NAFP, APFN, NPAF, FPNA, NPFA, and APNF showed a strong salty and umami taste. Therefore, the PNFA, NAFP, APFN, NPAF, FPNA, NPFA, and APNF are desirable methods for making EHVP with a salty and umami taste.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.5
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• pp.629-635
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• 2007

Response surface methodology (RSM) was used for the analysis and optimization of the production process of Kochujang added with Maesil extract. The process variables were the amount of Maesil extract ($0{\sim}8%$) and red pepper powder ($6{\sim}10%$). pH and all color characteristics (L*-, a*-, and b*-value) decreased but titratable acidity and water activity increased with the addition of Maesil extract. Amino nitrogen content appeared to decrease with the addition of red pepper powder. The highest sensory flavor score was obtained when 2.20% Maesil extract and 8.62% red pepper powder were blended, the highest sensory taste score with 6.63% Maesil extract and 9.50% red pepper powder, and the highest sensory color score with 7.80% Maesil extract and 8.62% red pepper powder respectively. The point chosen as representative of the optimal area corresponds to $X_1=3.60%,\;X_2=10%\;and\;X_1=4.08%,\;X_2=9.96%$ for physicochemical and sensory quality, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.3
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• pp.401-409
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• 2004

Two experiments were conducted to evaluate the effects of a complex Lactobacilli preparation on performance, resistance to E. coli infection and gut microbial flora of weaning pigs. In exp. 1, twelve pigs (7.65$\pm$1.10 kg BW), weaned at 28 d, were randomly allotted into 2 groups and placed in individual metabolic cages. During the first 7 d, one group of pigs was provided ad libitum access to water containing $10^5$ colony forming units (CFU) Lactobacilli per ml and the control group was provided tap water. The Lactobacilli preparation included Lactobacillus gasseri, L. reuteri, L. acidophilus and L. fermentum, which were isolated from the gastrointestinal (GI) tract mucosa of weaning pigs. On d 8, 20 ml of $10^8$ CFU/ml E. coli solution (serovars K99, K88 and 987P at the ratio of 1:1:1) was orally administered to each pig. Diarrhea scores and diarrhea incidence were recorded from d 7 to 14. On d 14, pigs were euthanized and digesta and mucosa from the stomach, duodenum, jejunum, ileum, cecum and colon were sampled using aseptic technique to determine microflora by culturing bacteria in selective medium. The results showed that Lactobacilli treatment significantly decreased E. coli and aerobe counts (p<0.01) but increased Lactobacilli and anaerobe counts (p<0.01) in digesta and mucosa of most sections of the GI tract. A 66 and 69.1% decrease in diarrhea index and diarrhea incidence, respectively, was observed in the Lactobacilli treated group. In exp. 2, Thirty-six crossbred Duroc$\times$Landrace$\times$Yorkshire piglets, weaned at 28$\pm$2 days, were selected and randomly allocated into 2 groups. There were 18 piglets in each group, 3 piglets in one pen and 6 replicates in each treatment with 3 pens of barrow and 3 pens of female piglet in each treatment. Piglets had ad libitum access to feed and water. The initial body weight of piglet was 7.65$\pm$1.09 kg. Dietary treatments included a non-medicated basal diet with Lactobacilli ($10^5$ CFU/g diet) or carbadox (60 mg/kg) as control. On d 21, six pigs per group (one pig per pen) were euthanized. Ileal digesta was collected to determine apparent amino acid digestibility. Microflora content was determined similarly to exp.1. The results showed that Lactobacilli treatment significantly improved average daily feed intake (ADFI) of pigs compared to carbadox (p<0.05) during the first 2 wks after weaning and average daily gain (ADG) and ADFI increased significantly (p<0.05) from d 8 to 14. Nitrogen and total phosphorus digestibility also increased (p<0.05). Bacterial counts were similar to exp. 1. The results indicate that the complex Lactobacilli preparation improved performance for 2 wks after weaning, enhanced resistance to E. coli infection, and improved microbial balance in the GI tract.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.6
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• pp.325-331
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• 2017

Adsorption experiments of carbon dioxide were performed on ZSM5 and Molecular Sieve 13X (MS13X) impregnated with Monoethanol Amine (MEA). Adsorption efficiency of $CO_2$ was investigated in a U type packed column with GC/TCD. The adsorption capacities of adsorbents are estimated in the temperature range of $30-80^{\circ}C$. The modified adsorbents was characterized by BET surface area, $N_2$ adsorption/desorption isotherms, X-ray diffraction and FT-IR. Surface analysis results showed that the impregnation method did not affect the crystallinity of any adsorbents. BET surface area of the MS13X impregnated amine decreased to $19.945m^2/g$ from $718.335m^2/g$. These reults showed that amine molecules were filled with the pore volume in MS13X, as a results restricting access of nitrogen into the pores. The MEA modified MS13X showed improvement in $CO_2$ adsorption capacity over the ZSM5 impregnated with MEA. The MS13X-MEA showed the highest adsorption capacity due to physical adsorption and chemical adsorption by amino-group content. This results also showed that adsorption capacity of MS13X-MEA increases with the temperature range of $60-80^{\circ}C$ compared with pristine MS13X.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.626-632
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• 2008

In an effort to improve the quality and palatability of kochujang, the physicochemical and microbial characteristics of kochujang were assessed when different quantities of citrus concentrate were added during fermentation. The moisture content of kochujang increased throughout the entire fermentation process. The pH of kochujang was reduced gradually, but the titratable acidity was increased to 10 weeks of fermentation. The amino-nitrogen and reducing sugar contents of kochujang to which citrus concentrate was added were higher than those of the control, and these values increased with increasing fermentation time. As the ratio of added citrus concentrate increased, the color of the kochujang brightened. The total cell and yeast counts were unaffected by the addition of citrus concentrate. Our sensory evaluation test showed that the addition of 6% citrus concentrate was the optimal condition for improving the quality of kochujang. In conclusion, the addition of citrus concentrate was desirable for the improvement of the quality and palatability of kochujang.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.297-302
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• 2008

In this study, Chrysanthemum indicum L. flower tea was prepared according to different pan-firing times (5, 7.5, 10, 12.5, and 15 min) and its quality characteristics were investigated. Total nitrogen and tannin contents increased with increasing pan-firing time, whereas chlorophyll and total amino acid (AA) contents decreased. The total AA contents of the samples ranged from 6,399 to 7,068 mg%, and the highest content (7,068 mg%) was found with the 10 min panfiring treatment. The AAs occurring in the C. indicum L. flower tea included glutamic acid and aspartic acid, which are desirable flavor components. As the pan-firing time increased, antioxidant activity as well as total polyphenol and flavonoid contents increased. The highest total polyphenol and flavonoid contents were found in the 15 min treatment at levels of 13.85 mg tannic acid equiv./g and 9.77 mg catechin equiv./g, respectively. The 15 min pan-firing treatment also had the highest total antioxidant activity at 19.33 mg ascorbic acid equiv. eg/100 g. Finally, based on sensory evaluations, the 10 min pan-fired C. indicum L. flower tea had the best overall quality.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.229-234
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• 2003

The traditional kochujang supplemented with mushrooms (Pleurotus ostreatus and Lentinus edodes) was prepared, and changes in quality characteristics during fermentation at ambient temperature were investigated. The moisture content of kochujang increased by addition of mushroom. The titratable acidity of mushroom-added kochujang was gradually increased during fermentation. Ethanol contents of mushroom-added kochujang decreased with the addition of oyster mushroom, but increased with the addition of oak mushroom. The amino-nitrogen contents increased gradually during fermentation, resulting in significantly higher contents of 9% mushroom-added kochujang than others. The a value of kochujang decreased greatly during fermentation, but L, a and b values showed significantly higher than the control. The growth of bacteria in kochujang was delayed by the addition of mushrooms. Bacterial and yeast counts at the end of fermentation were not influenced by the addition of mushrooms. Sensory evaluation test revealed that color and flavour of kochujang were improved by the addition of mushrooms, and higher score was obtained from the addition of oyster mushroom compared to oak mushroom.

• Korean Journal of Medicinal Crop Science
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• v.9 no.4
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• pp.275-279
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• 2001

The contents of chemical components such as total nitrogen, total amino acid, chlorophyll, vitamin C and free sugar were somewhat higher in $CO_2$ and $N_2$ gas treatment than those of other treatment. However, the contents of tannin and caffeine did not show any different in the 5 treatments. ${\gamma}-aminobutyric$ acid(GABA) and alanine accumulated in tea leaves under anaerovic condition. The content of GABA acid with ${CO_2\;and\;N_2}$ gas treatment was higher 8-6 times with values of ${264{\sim}215mg/100g}$ than in control (35mg/100g). The scores of sensory test was not different between anaerobic treatment and control. Consequently, tea mading within ${N_2\;and\;CO_2}$ gas treatment after plucking was considered to be the best green tea in terms of functional nature as well as taste nature.

• Applied Biological Chemistry
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• v.24 no.1
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• pp.21-28
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• 1981

Brewing method and quality of 15 samples of traditional Kochuzang in Junrabook-do area were investigated. Average combination ratio of glutinous rice: Meju (soybean Koji): red pepper powder was 2 : 0.7 : 1.1. In order to improve the taste of Kochuzang, some amount of natural soysauce was added in the Kochuzang at early stage of fermentation. Average content of sodium chloride was 7.32%; amino nitrogen, 123.3%; total sugar, 31.9%; reducing sugar, 19.4%; ethyl alcohol, 1.13% and the activity of acid protease was 0.07; liquefying amylase, 9.67 and saccharogenic amylase was 15.82. Five samples were selected as excellent Kochuzang through sensory evaluation. These samples were similarly strong in hot and sweet taste with alcoholic flavor, glossy surface and brownish red color.