• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.379-389
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• 2008

This study was conducted to assess the microbiological quality of raw and cooked foods served in the elementary school food service. Raw and cooked food samples were collected from 11 selected elementary schools in both June to July and September to October of 2005. Petrifilm plates were used to determine (in duplicate) total aerobic colony counts (PAC), Enterobacteriaceae (PE), coliform counts (PCC), and E. coli counts (PEC). Heavy contamination of Enterobacteriaceae (from 0.08 to 7.40 log CFU/g) and total coliform (0.50 to 6.52 log CFU/g) were observed in raw materials and cooked foods. Escherichia coli (E. coli) were detected in the sample of currant tomato (3.70 log CFU/g), sesame leaf (3.59 log CFU/g), dropwort (0.20 log CFU/g), crown daisy (3.15 log CFU/g), parsley (3.00 log CFU/g), peeled green onion (1.74 log CFU/g), frozen pork (0.65 log CFU/g), frozen beef (0.20 or 1.50 log CFU/g), chicken (1.78 log CFU/g), and young radish leaf seasoned with soybean paste (1.24 log CFU/g). Multiplex PCR system was used to determine the food-borne pathogens: Salmonella spp., Bacillus cereus (B. cereus), E. coli O157:H7, Staphylococcus aureus, Listeria monocytogenes (L. monocytogenes), Vibrio parahaemolyticus, Campylobacter jejuni (C. jejuni), Shigella spp., B. cereus was detected in 19 samples of raw materials and 8 samples of cooked foods. With regard to quantitative analysis, B. cereus counts exceeded 5.46, 3.48 and 1.79 log CFU/g in sesame leaf, peeled green onion and seasoned mungbean jelly, respectively. E. coli O157:H7 was detected on 2 samples of frozen beefs, and its biochemical characteristics of one beef sample was confirmed with API 20E kit (93.7%). L. monocytogenes was detected in fried rice paper dumpling, but the presumptive colonies were not detected onto the conventional plate. C. jejuni was detected in peeled & washed onion.

• The Korean Journal of Food And Nutrition
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• v.24 no.1
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• pp.124-131
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• 2011

We analyzed content and peptides in order to investigate the productivity from Cheonggookjang(fast-fermented soybean paste), fermenting it for 180 hours at $40^{\circ}C$. Results showed that pH was 7.07 at the start and became 7.41 in 24 hours, it eventually increased to 8.63 after 180 hours. Acidity was 0.2 in 12 hours, 0.5 in 12 hours, and then remained on 0.1 thereafter. Total sugar was 1.54 mg/$m\ell$ at the start, but it gradually decreased to 0.76 mg/$m\ell$ after the lapse of 48 hours, and 1.0 mg/$m\ell$ in 120 hours, and finally 0.8 mg/$m\ell$ in 180 hours. Reducing sugar was 0.14 mg/$m\ell$ at the start, and 0.88 mg/$m\ell$ after the lapse of 24 hours, 0.64 mg/$m\ell$ in 48 hours, 0.26 mg/$m\ell$ in 72 hours, and showed no definite change untill 180 hours. The amount of free amino acid was $0.19\;{\mu}M/\ell$ at the start, and $4.88\;{\mu}M/\ell$ after the lapse of 72 hours, $4.5\;{\mu}M/\ell$ in 120 hours, and then it rapidly decreased to $0.23\;{\mu}M/\ell$ after180 hours. Absorbance of soluble protein and peptide at 280 nm was 12.4 in 48 hours, 31.12 in 120 hours, and 31.12 in 180 hours. HPLC revealed that in the fermentation process, large molecular proteins are hydrolyzed into small peptides and amino acids, and after the lapse of 48 hours the pattern became almost the same. The protease activity of Cheonggookjang was 0.011 unit/$m\ell$ after the lapse of 36 hours and then it decreased. The result shows as Cheonggookjang started its deamination of amino acid in 100 hours, it is desirable to produce peptide within 100 hours of its fermentation.

• Food Science and Preservation
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• v.17 no.5
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• pp.688-697
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• 2010

We investigated the cholesterol-lowering and body-weight loss effects of Cheonggukjang fermented using Bacillus subtilis DJI in rats fed a high-fat/high-cholesterol diet for 4 weeks. Weight-matched male Sprague-Dawley rats were assigned to one of four groups: a normal diet group (N), a high-fat/high-cholesterol diet group (HFC), a high-fat/high-cholesterol diet with DJI Cheonggukjang group (HFC-SCK), and a high-fat/high-cholesterol with commercial Cheonggukjang group (HFC-CCK). All of body weight and liver and adipose tissue weights increased in animals fed a high-fat/high-cholesterol diet, but decreased significantly in rats fed Cheonggukjang powder, compared with the HFC group. Food intake was lower in the HFC group than in the N group, and that of the HFC-CCK group was the lowest among the four groups. Serum total cholesterol levels were significantly lower in the Cheonggukjang-powder fed groups than the other groups. Serum phospholipid and HDL-cholesterol concentrations were significantly decreased in HFC animals and were markedly increased upon feeding of a Cheonggukjang-containing-diet. Levels of serum LDL-cholesterol, the atherogenic index, and cardiac risk factor assessment indications tended to be decreased in Cheonggukjang powder-fed groups, compared with the HFC group. The total cholesterol level in liver tissue was increased by feeding of a high-fat/high-cholesterol diet, and was significantly reduced when Cheonggukjang powder was present in the diet. The levels of total lipids and triglycerides in adipose tissues were lower in the HFC-SCK group than in the HFC group, whereas no significant differences were evidence when the HFC and the HFC-CCK groups were compared. Fecal weight, moisture level, and total lipid content increased in animals fed Cheonggukjang powder. The activities of HR-LPL and TE-LPL in adipose tissues were increased in the HFC group compared with the Cheonggukjang powder-fed groups. These results indicate that dietary Cheonggukjang may improve lipid metabolism and prevent obesity and hyperlipidemia.

• Food Science and Preservation
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• v.30 no.6
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• pp.1056-1071
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• 2023

This study aimed to investigate the quality and microbial population changes for 90 days under two fermentation conditions, outdoors and indoors (35℃), with starters (single or mixed) in soybean paste. Bacillus velezensis NY12-2 (S1), Debaryomyces hansenii D5-P5 (S2), Enterococcus faecium N78-11 (S3), and their mixtures (M) were used for the makjang fermentation. The content of amino-type nitrogen among the makjang samples was highly shown in the indoors, followed by M, S3, and S2. The glutamic and aspartic acid contents in the M sample fermented in the indoors showed the highest values of 867.42±77.27 and 243.20±15.79 mg/g, respectively. By the electronic tongue analysis, the M sample fermented in the indoors exhibited lower saltiness and higher umami than the others. Consequently, we expect that using mixed strains, such as Bacillus, Debaryomyces, and Enterococcus, under constant conditions showed potential to the quality improvement of soy products.