• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.274-279
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• 2001

Generally, non-aflatoxigenic fungi, such as Aspergillus oryzae, and Aspergillus are main microflora in Korean traditional fermented foods including Meju and soybean paste, but sometimes, Aspergillus flavus and Aspergillus parasiticus can be contaminated and accumulated aflatoxins during fermentation and storage. So the screening of aflatoxigenic strains in fermented traditional food is very important to improve the sanitary quality of those foods. In this work, we screened aflatoxin producing fungi from commercial Meju and soybean paste in Western Gyeongnam by immunoassay. Samples were randomly purchased from market of the commercial Meju(10 EA) and soybean paste(20 EA) in nine areas of Western Gyeongnam. Of the samples collected,24 strains and 22 strains of Aspergillus sp. were isolated from Meju and soybean paste, respectively. The isolated strains were cultured on SLS media at $25^{\circ}C$ for 15 days. The cultured broth were extracted with ethyl acetate and were analysed to determine aflatoxin B$_1$(AFB$_1$) by direct competitive ELISA(DC-ELISA). Six strains(25%) isolated from Meju, and 2 strains(9%) isolated from saybean paste, were confined as aflatoxin producing strains. The average range of aflatoxin productivity of isolates from Meju was 54.6 $\pm$ 38.7 ng/ml and that from soybean paste was 11.1 $\pm$ 8.6 ng/ml, respectively. Among them, isolated strain No. M-5-4 produced a high level of AFBl and showed 98.26 ng/ml of AFB$_1$. Every isolates were also re-confined their AFB$_1$productivity by thin layer chromatography(TLC). The TLC results also showed same trend as DC-ELISA results. As the above results, the screening of hazard mycotoxigenic fungi from traditional fermented foods should be necessary for the safety and the application of HACCP system in the food manufactory in Korea.

• Journal of Animal Environmental Science
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• v.14 no.1
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• pp.31-38
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• 2008

Ammonia gas is one of the malodorous gases from swine production facilities, such as manure storage tank, manure fermentation facilities, and livestock houses, etc. Ammonia gas from swine house is being emitted at relatively low concentrations throughout the year. Therefore, livestock facilities were continuously ventilated to supply fresh air for respiration of the animals internal the livestock facilities. The swine facilities need very high ventilation rate to control the inside environmental conditions. The deodorization system of the livestock facilities must be developed considering the ventilation rates. The odor abatement system was installed in order to improve the internal environment of the naturally ventilated growing-finishing pig house. The system which distributes the deodorized air into inner space of the swine house by using plastic duct was installed. Since the internal environment, effected by the operation of the odor abatement system, is monitored by closing the winch curtain installed on the side wall of the pig house, the experiment was practiced at the season when the internal environment becomes aggravated, winter. The effects on the improvement in the internal environment of swine house by operating the odor abatement system are as follows ; 1. By re-distributing the air which was deodorized by the odor abatement system installed in the pig house, the result showed that the concentration of ammonia gas is decreased approximately 33.3% compared with that before operating odor abatement system. 2. The effect on the pig house's ammonia gas reduction was found that the ventilation rate was less than $0.5m^3$/min head. The effect of the operation of the odor abatement system showed to be scarce when the ventilation rate increases because of the influx of external fresh air makes the quantity of diluted air more than those of the odor abatement system. 3. The perishment rate of the pigs which were brooded until slaughtering decreased about 3.8% by operating the odor abatement system in the growing-finishing pig house. Also, after operating the odor abatement system, the stinging of the eyes, suspension dust, etc were decreased when going into swine house for management.

• Food Science of Animal Resources
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• v.24 no.1
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• pp.92-96
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• 2004

pH, Campylobacter spp., Salmonella spp. and Escherichia coli of under-utilized broiler viscera silage added with table sugar during storage at 25$^{\circ}C$ were investigated. pH of silage with 0 and 1 %(w/w) table sugar increased continuously after day 2, but that of 3, 4 and 5% remained 4.0∼4.2 after decrease from 5.2 at day 0. The Campylobacter spp. count of 0% was 8.21 at day 4, however that of 3 and 5% showed 7.56 and 7.38 logCFU/mL, respectively. The Salmonella spp. of 0% maintained 5.8∼6.8 logCFU/mL during fermentation, but that of 3 and 5% was not detected after day 4. The initial E. coli count of silage without table sugar was 5.8 log CFU/mL, but reduced to 4.1 log CFU/mL at day 2, and maintained at the level between 4.0 and 5.0 log CFU/mL, thereafter. However, E. coli was not detected in the silage with 3 and 5% table sugar after day 2. The counts of Campylobacter spp., Salmonella spp. and Escherichia coli of under-utilized broiler viscera silage reduced markedly by adding table sugar. It was proved that the possibility of microbiologically safe broiler offal silage as a potential resource for animal feed materials was improved.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.762-771
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• 1996

Chemical and sensory characteristics of kakdugi which was prepared with various radish cultivars and harvesting seasons were analyzed during 7-day storage. Average pH of small radish cultivar kakdugi was higher than that of large ones, and total acidity was lower in small ones. Reducing sugar content was the highest in kakdugi of autumn radish. Organic acids such as lactic, succinic and fumaric acid analyzed by GC increased until the third day of fermentation, whereas volatile isothiocyanates analyzed by GC/MS continued to decline. There was a significant difference in flavor characteristics of large radish kakdugi across seasons, in contrast to no significant difference in those of small radish kakdugi except sweet taste and reducing sugar content in which interaction existed between season and cultivar. Score of overall acceptability was higher in small radish than large ones with Dongja showing the highest score of overall acceptability. Overall acceptability of autumn Dongja kakdugi was positively correlated with radish kakdugi odor and sour odor, respectively, but negatively with total acidity, lactic acid content, sweet taste and pungency, respectively. By multiple regression analysis, overall acceptability in spring Dongja kakdugi is expressed as a function of overall acceptability = -0.1115 + 1.2519 savory taste + 1.5159 malic acid -0.0054 total isothiocyanate + ${\varepsilon}$.

• Korean journal of food and cookery science
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• v.14 no.5
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• pp.589-596
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• 1998

This study was carried out to evaluate the quality attributes of soy yogurts prepared by different types of oligosaccharides (fructooligosaccharide, galactooligosaccharide , isomaltooligosaccharide) and Bifidobacteria (B. bifidum B. breve, B. infantis) containing enzyme treated soy protein isolate in terms of pH, titratable acidity, total number of viable cells of Bifidobacteria, ${\alpha}$-galactosidase activity, organic acids, volatile compounds. The pH values of soy yogurts fermented by B. bifidum showed the highest significantly but those fermented by B. infantis showed the lowest significantly, while the titratable acidity of soy yogurts were vice versa. The viable cells of Bifidobacteria of all soy yogurts showed more than 10$\^$9/ CFU/ml and soy yogurts fermented by B. infantis showing below pH 4.6 showed more than 10$\^$9/ CFU/ml after storage at 4$^{\circ}C$ for 7 days. The activity of ${\alpha}$-galactosidase showed the highest in the culture of B. infantis among the Bifidobacteria tested. Among the Bifidobacteria tested, the contents of lactic acid and acetic acid showed the highest in soy yogurts fermented by B. infantis but citric acid and propionic acid were the lowest. Among the Bifidobacteria tested, the contents of n-hexanal showed the highest in soy yogurts fermented by B. breve and a little amounts of acetaldehyde were present in all soy yogurts.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.466-471
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• 2010

This study investigated the effects of dietary supplementation of fermented apple pomace (FAP), fermented pear pomace (FPP), fermented orange pomace (FOP), and fermented Angelica keiskei Koidz pomace (FAKP) on performance, shelf life, fatty acid composition and cholesterol in broiler chickens. A total of 600, 1-day-old male broiler chicks (Cobb strain) were randomly divided into six groups with four replicates of 30 birds each. There were five treatment groups: control (C), FAP (1.0%, T1), FPP (1.0%, T2), FOP (1.0%, T3), and FAKP (1.0%, T4). The body weight of the broiler chickens fed FAP diet was higher (1,758 g) than the other treatments. There was no difference in the thiobarbituric acid reactive substances (TBARS) in chicken meat between all groups at days 1, 3, and 5 of storage, while the FAP-supplemented group displayed lower TBARS values at day 7. There was no significant difference in fatty acid composition between the groups but the cholesterol content of chicken meat was lower than the control groups. These results suggest the possibility that FAP could be used as a functional feed to improvement the quality performance of broiler chickens.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.926-934
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• 2006

The base for preparing oyster hydrolysate-added yogurt was consisted of whole milk (1,000 mL), skim milk (44.05 to 42.05 g), enzymatic oyster hydrolysates powder (OHP, 0 to 2.0 g) and pectin. The yogurt base was fermented with 7 kinds of starter cultures (3% based on yogurt volume), such as Lactobacillus acidophilus, lactobacillus bulgaricus, lactobacillus casei, Lactobacillus fermentum, Lactobacillus pentosus, Streptcoccus thermophilus and the mixed starters (L. bulgaricus and S. thermophilus) at optimal temperature. Processing condition and quality characteristics of the yogurt were evaluated by analyzing pH, titratable acidity, viscosity, viable cell count, functional properties and sensory evaluation. The results suggested that the optimal conditions for preparing the good quality yogurt revealed the mixed starters (L. bulgaricus and S. thermophilus) for starter culture, 1.0 g of 3 kDa hydrolysate for amount, and 5.5 hrs for fermentation time. The good quality yogurt showed 4.31 for pH, 1.07% for titratable acidity, 469 cps for viscosity and $4.9{\times}10^8\;CFU/mL$ for viable cell count. The hydrolysate-added yogurt was 2 times higher in ACE inhibitory and antioxidant activities than commercial yogurt, and kept good quality during storage of 15 days at $5^{\circ}C$.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.642-649
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• 2006

The browning of soy sauce is caused by the reaction of amino-carbonyl between amino-compounds and reducing sugar. Only a few studies have investigated the formation of melanoidins in UHYUKJANG. The objectives of this study were to analyze the brown pigment of UHYUKJANG and to investigate the characteristics of UHYUKJANG in comparison with soy sauce and model melanoidins. The samples were ripened for 0, 60, 120, 180, 240, 300 and 360 days at 4$^{\circ}C$ and 20$^{\circ}C$. The pH, absorbance at 420 nm absorbance ratio of 400 to 500 nm and UV-VIS spectra as an index of color intensity were measured. Additionally, L, a and b values of the samples and the amount of 3-Deoxyglucosone(3DG) in the samples were measured. The pH of both soy sauce (from 6.26 to 5.52) and UHYUKJANG (from 6.13 to 5.11) rapidly decreased during the first 60 days of aging and was also affected by storage temperature. The absorbance of samples at 420 nm increased during the aging process, reaching its maximum after 180 days, regardless of sample and temperature. On the other hand, the intensity of brown color in the samples increased with increasing aging period according to the results of absorbance ratio (soy sauce: 1.37 to 5.29, UHYUKJANG: 1.37 to 5.02). The L value of soy sauce increased during the aging process and was maximized after 240 days at 4$^{\circ}C$ and 180 days at 20$^{\circ}C$, but decreased thereafter. There was no significant difference in L value of UHYUKJANG, regardless of aging period and temperature. On the other hand, the b value did not reveal any significant change during aging, but the a value increased until 120 days of aging in the other samples except for UHYUKJANG at 20$^{\circ}C$. The average amount of 3DG separated from soy sauce was 5.65 mg%, and from UHYUKJANG was 3.74 mg%. These results indicated that the browning of UHYUKJANG was also caused by melanoidins produced by the reaction of amino-carbonyl during the fermentation process.