• Journal of Food Hygiene and Safety
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• v.32 no.2
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• pp.114-122
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• 2017

N-nitrosamines can be produced in the process of heating, processing, storage and packaging. Migration specifications for N-nitrosamines exist only for rubber baby bottle nipples, which are regulated by the Ministry of Food and Drug Safety (MFDS). There is no regulation for other food contact substances (FCS) and studies on N-nitrosamines migration from FCS are rather limited. A pilot study showed an increase in N-nitrosamines contents when cooking instant noodles. Thus, the migration from the packaging was suspected and it was necessary to monitor the migration of N-nitrosamines from food packaging materials and to examine the change in N-nitrosamines contents when cooking instant foods. Three N-nitrosamines, NDMA (N-nitrosodimethtlamine), NDEA (N-nitrosodiethylamine), NDBA (N-nitrosodibutylamine), were analyzed in migration test solutions from plastics such as polyethylene, polypropylene and polystyrene, papers and aluminium containers. In all test solutions, N-nitrosamines were detected less than method quantitation limits (MQLs). Food samples were also investigated to ensure that there is no effect from food contact substances when cooking instant foods. In retort sauces such as curry, black soybean sauce and tomato sauce, NDMA concentration was ranged from 0.54 to $3.81{\mu}g/kg$, but there were no significant differences between unheated and heated samples. However, the NDMA contents were significantly increased in most of the instant noodle samples tested when cooked (p < 0.05). No effects from the food contact substances or cooking water was observed. Only when the seasoning powder and noodles were cooked together was NDMA detected. Individual components (noodle, seasoning powder or dried vegetable) or other combinations such as noodles and dried vegetables did not generate N-nitrosamines. Therefore, it is speculated that NDMA may be formed from the precursors in noodles and seasoning powders when they are solubilized in a medium of water.

• Journal of Life Science
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• v.33 no.6
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• pp.481-489
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• 2023

The taste and quality of soy sauce, a fermented liquid condiment, is greatly influenced by microbial metabolism during fermentation. To investigate the microbiological characteristics of ganjang during the initial fermentation process, we prepared meju (fermented soybean) blocks fermented with starter cultures and solar salts and analyzed the microbial community quantitively using 16S rRNA gene profiling from ganjang that had been fermented over a five-week period. The ganjang samples were collected and analyzed after soaking for week one (1W), three (3W), and five (5W) weeks. We found that Halomonadaceae was significantly higher in the 1W group (89.83%) than the 3W and 5W groups (14.46%, and 13.78%, respectively). At a species level, Chromohalobacter beijerinckii and Chromohalobacter canadensis were the dominant species in the 1W group but several taxa such as Bacillus subtilis, Pediococcus acidilactici, and Enterococcus faecalis were more abundant in the 3W and 5W groups. Pearson correlation analysis of the relative abundance of the bacteria showed a negative correlation between Chromohalobacter and two bacterial genera Bacillus and Enterococcus. Beta-diversity showed a statistical distinction between the 1W and the 3W and 5W groups, while no significance was evident between the 3W and 5W groups. Linear discriminant effect size analysis was used to identify biomarkers and significant differences in the relative abundance of several halophilic bacteria, Bacillus sp. and lactic acid bacteria at 1W, 3W, and 5W, recpectively, which indicates the important role of the bacterial community at these time points.

• Applied Biological Chemistry
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• v.41 no.3
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• pp.201-207
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• 1998

In order to evaluate the effects of addition of soybean boiling waste liquor (SBWL) and sugar and inoculation of the lactic acid bacteria and yeast starter culture in Korean traditional kanjang mash, three types of kanjang were prepared in a clay pot of 100 l volume and compared the characteristics of lactic acid fermentation. The mashing compositions of the types of kanjang were as follows: (1) control treatment mash was prepared with meju : 20% salt solution (1:4) and SBWL, (2) kanjang mash with 3.5% added sugar to the control type mash and (3) kanjang mash with 3.5% added sugar and inoculation of the lactic acid bacteria and yeast starter culture 35 days after mashing to the control type mash. (1), (2) and (3) of kanjang mash were found to be effective in increasing the lactic acid content and improving the organoleptic characteristics of kanjang. But the effect of yeast starter culture was not clear because osmophilic yeasts were inhibited by metabolite(acetic acid) produced by lactic acid bacteria. The lactic acid content of (1), (2) and (3) kanjang was 2.05, 2.38 and 2.91% respectively in 90 day-matured kanjang.

• Food Science and Preservation
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• v.15 no.2
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• pp.293-299
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• 2008

Bacillus sp. SP-KSW3 is an auxothroph bacteria that is being used for starter in fermentation. Physico-chemical characteristics, enzyme activities, ACE inhibitor and antimutagenicity in fermented soybean (Kanjang) inoculated with Bacillus sp. SP-KSW3 starter was investigated for the ripening duration of fermentation. Tyrosinase and ACE showed 7% higher activity degree on the Kanjang maturated fermented 2 years with Bacillus sp. SP-KSW3 (Type I) than test field than Kanjang maturated 2 years (control). For antimutagenicity using S. enterica serovar Typhimurium TA100 against MNNG and NPD showed 35.17% and 28.37% (Type I). Similarly, S. enterica serovar Typhimurium TA98 was used against NPD and NQO showed 25.48% and 21.64% (Type I), respectively. Hydrogen donating ability 2 year for maturing (Type I) appeared most highly in the test eulogy 83.1% which it makes. Daidzin of isoflavone in fermented soybean showed similarly. Genistein was not detected The initial test field for daidzin and genistein contained 3.95 mg/kg and 1.25 mg/kg (Type I), respectively.

• Applied Biological Chemistry
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• v.43 no.1
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• pp.29-33
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• 2000

This study was carried out to investigate the effect of glutaminase added to Doenjang, Kochujang and Kanjang in manufacturing. The consequential changes of L-glutamic acid and amino nitrogen contents were periodically analysed during aging. L-Glutamic acid contents in Kochujang, Doenjang and Kanjang aged for 45 days increased to 671.8%, 298.1% and 193.4% with glutaminase and also increased to 363.1%, 159.2% and 35.7% as compared with those without glutaminase. The 0.01% addition of glutaminase to Kochujang made L-glutamic acid content increased more than 3 times. The increase ratio of amino nitrogen was 216%, 120.8% and 84.5% in Kochujang, Kanjang and Doenjang with glutaminase which aged for 45 days, respectively. The effect of glutaminase added was the greatest in Kochujang. It increased to 35.7%, 8.4% and 40.3% as compared with those without glutaminase. The results of sensory evaluation showed that the products were favorably affected in taste, flavor and acceptability by glutaminase added.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1612-1617
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• 2009

Aspergillus sp. 101 was isolated from the Korean traditional soybean paste for the production of a salt-tolerant protease. The optimal condition for the production of a salt-tolerant protease was determined with various energy sources such as carbon, nitrogen, and protein, and at different culture conditions such as temperature, pH, incubation time and NaCl concentration. The most favorable organic nitrogen sources were 2% defatted soybean flour (DSF) and soy protein isolate (SPI). Optimal pH and temperature were pH 6.0 and $25{\sim}27^{\circ}C$, respectively. Therefore, Aspergillus sp. 101 protease was a mild acid (or neutral) protease. Protease production was the highest at 0.1% concentration of $CaCO_3,\;K_2HPO_4$ and Arabicgum. Aspergillus sp. 101 could grow in culture medium at 15% NaCl concentration and produce a salt-tolerant protease even at 7% NaCl. The cell mass and protease activity of Aspergillus sp. 101 cultured in a modified medium was comparatively higher in Czapek dox and protease producing media. Hence, Aspergillus sp. 101 protease can be utilized in soy or fish sauce industry as a salt-tolerant protease starter.

• Journal of the Korean Home Economics Association
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• v.17 no.1
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• pp.22-28
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• 1979

The phyio-chemical properties of Ion exchange salt, crude salt, particaly refined salt, and Isoized salt were determined. The basic amount of salt used in cooking were standardized . Acceptabilities as to the taste and saltiness of food prepared with the standard amounts of various kinds of salt were compared. Whereupon, the following conclusion was obtained. 1) Crude salt showed 12.23 per cent water content, the highest among the kinds of salt examined, while particaly refined salt had 2.53% water content. Refined salt, Ion exchange salt, and Iodized salt showed 0.36%, and 0.28%, respectively. 2) Where the same amount of salt was dissolved in the same amount of water, crude salt and partialy refined salt were dissolved twice as Ion exchange salt of fine-grain form, refined salt, and Iodized salt. In actual cooking, Ion exchanges salt and refined salt are used only half as much as raw salt, and it can be said that the time required for dissolving salt is the same. 3) The comparison between content and weight of various kinds of salt showed that the weights of Ion exchange salt, Iodized salt, and refined salt were two times as heavy as crude salt and partialy refined condition of same content. 40 The threshold concentration of salt is the sensed degree of saltiness. Different concentrations were recorded for various for various kinds of salt, the threshold concentration of Ion exchanges salt showed the lowest degree of 0.05, while that of partialy refined salt was 0.09 equivalent to 1.8 times that of the former. 5) Experimental cooking involving various kinds of salt indicated that where salt was used accurately, soup, vegetables, kimchi, and soybean sauce which were prepared with Ion exchanges salt showed the best acceptability , but no statistical differences could be noted among sarious kinds of salt used in preparing those foods.

• Parasites, Hosts and Diseases
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• v.47 no.3
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• pp.281-285
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• 2009

Paragonimiasis typically results from the consumption of raw or improperly cooked crustacea, especially crabs and crayfish. Although previously endemic in Korea, the prevalence of this disease decreased in the early 1970s because of educational campaigns and fewer intermediate hosts as a result of ecological changes. Recently, we were presented with a family where all members were infected with Paragonimus after ingestion of Kejang (= drunken crab). The mother was hospitalized for general myalgia and weakness first, followed by the father, who was hospitalized for dyspnea 2 month later. After the parents were diagnosed with paragonimiasis, we recommended their daughter to visit our hospital for a checkup, because they all had eaten freshwater crabs soaked in soybean sauce. She complained of generalized myalgia, fever, and pleuritic pain, and was also diagnosed with paragonimiasis. Peripheral blood of the 3 patients revealed hypereosinophilia, and computed tomography (CT) scans of their chests showed pleural effusion. The results of antibody tests by ELISA were positive for paragonimiasis. We report here the case series of familial paragonimiasis in a modern urban city, rather than in a typical endemic area.

• Preventive Nutrition and Food Science
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• v.3 no.3
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• pp.221-224
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• 1998

Toha-jeot, salt-fermented Toha shirmp(caridina denticulata denticulata DeHAAN) is a traditional fermented food in Korea. Samples of Toha-jeot used in the present study were a low-salt group of 15% sodium chloride(L), a high-salt group of 23% sodium chloride(H), a 50% conventional soybean sauce group(S), a low-salt group contraining 2% wheat bran (W2%-L) , a high -salt group containing 2% wheat bran(W2%-H), a low-salt group containing 4% wheat bran(W4%-L)and a high-salt group containing 4% wheat bran (W4%-H). These seven groups were refrigerated at 4 $\pm$1$^{\circ}C$ and then taken out for analysis at theree month intervals. We investigated the functional components of Toha-jeot during fermentation . Long fermentation of Toha-jeot lowered the viscosity of chitin and tended to reduce the distribution of molecular weight. THe formation of chitin oligosaccharides on the other hand, increased significantly. After nine months of fermenttion, chitin oligosaccharides(M.W. 823~1789) constituting 24.75% of Toha chitin were produced in the sample of W2%-H. During the same period, chitin oligosaccharides(M.W.1436-1879) constituting 66.30% of Toha chitin were produced in the samples of S. However, chitin oligosaccharides were not produced in Jeotsaeu-jeot made of sea-water shrimp when fermented for six months.

• Preventive Nutrition and Food Science
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• v.16 no.2
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• pp.165-173
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• 2011

Five types of meju were prepared from 100% defatted soybean (DFSG0), a mixture of 90% DFS and 10% glasswort (DFSG1), a mixture of 80% DFS and 20% glasswort (DFSG2), a mixture of 70% DFS and 30% glasswort (DFSG3), and a mixture of 60% DFS and 40% glasswort (DFSG4). Five types of kanjang were separately prepared from the 5 types of meju by ripening in brine for 6 months. The contents of certain minerals (Mg, Ca, Fe, Mn, and Zn), organic acids (citric acid, malic acid) and the antioxidative effects in the kanjang were increased in proportion to the glasswort content in the meju. However, the free amino acid contents in the kanjang were reduced in proportion to the glasswort content in the meju. DFSG1- and DFSG2-kanjang did not show distinct differences from DFSG0-kanjang based on aroma, flavor, and taste that were compared simply by panel tests. The bacterial and fungal community in the fermented meju and kanjang was not affected by the addition of glasswort to the meju-making process. Bacteria belonging to the Lactobacillus and Bacillus genera and the Lactobacillus family predominated, and yeasts belonging to the Saccharomyces genus and fungi belonging to the Aspergillus genus predominated in the fermented meju and kanjang. In conclusion, the glasswort was a supplement that nutritionally improved the kanjang (except for free amino acid contents) but didn't influence the growth of microorganisms that are responsible for the fermentation of meju and kanjang.