• 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.

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.245.2-245
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• 1999

No Abstract, See Full Text

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1447-1458
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• 2009

Volatile extracts obtained from traditional Chinese-type soy sauces prepared with soybean (SSSB) and defatted soy meal (SSDSM) by solid phase microextraction (SPME) and direct solvent extraction (DSE) were analyzed by gas chromatography-mass spectrometry (GC-MS). The volatile flavor compounds and relative contents of different chemical classes detected in SSSB and SSDSM were compared for their differences. Results showed that significant differences in both constituents of volatile flavor compounds and relative contents of different chemical classes were observed for both kinds of soy sauces. A total of 152 and 131 compounds were identified in SSSB and SSDSM, respectively, and 102 volatile flavor compounds were common in both kinds of soy sauces. Moreover, relative contents of acids, aldehydes, esters, furan(one)s, miscellaneous compounds, phenols, pyrazines, pyrrol(idinon)es, and sulfur-containing compounds in both kinds of soy sauces were all significantly different.

• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.313-317
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• 1998

This study was perfonned to investigate the possible effect of Bacillus subtilis which is the predominant species of bacteria in Korean soy sauce, soy paste, and Meju (soybean cake) on the growth and aflatoxin production of Aspergillus parasiticus ATCC 15517. The microorganisms were grown in a modified APT broth and incubated at $30^{\circ}C$ for 12 days. Aflatoxins were determined using high performance liquid chromatography (HPLC). A remarkable inhibition of the growth of Aspergillus parasiticus was observed during the incubation period when in the presence of B. subtilis (mixed culture). Dry mycelial weight in the mixed culture was significantly reduced by 85.3% in comparison to the control at the end of the incubation period (p<0.01). Lower levels of aflatoxins were found in the mixed culture than in the monoculture. At the end of the incubation period aflatoxin production was significantly inhibited by more than 50% (p<0.05). These results indicate that B. subtilis mainly inhibites the growth and aflatoxin production of toxigenic Aspergillus in Meju, soy sauce and soy paste. Although its effect on aflatoxin production was less pronounced, we could expect more inhibition by another bacteria related with fermentation in Meju.

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.99-111
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• 2000

The purpose of this study was to assess the qualities of cook/chilled soy sauce-glazed soybean curd with various packaging conditions as a trial to develop health-oriented convenience foods. The effects of three packaging methods, linear low density-polyethylene (LLD-PE), top sealing, and modified atmosphere packaging(MAP) on the shelf-life of HACCP-based cook/chilled soy sauce-glazed soybean curd were evaluated during 20 days of chilled storage in terms of time-temperature, microbiological (total aerobic plate count, psychrotrophic plate count, coliform, and fecal coliform count), chemical(pH and peroxide value(POV)), and sensory evaluation. The results of microbiological and chemical analyses were within the limits of the microbial and chemical standards for all phases after cooking. No significant differences were detected in microbial counts of the samples for all three packaging methods. However, sensory evaluation indicated that the top sealing and MAP methods showed a longer shelf-life than LLD-PE packaging. Recommended shelf-life of the product was 12 days for LLD-PE packaging, and 16 days for both top sealing and MAP. In conclusion, MAP was considered as the most effective packaging method for assuring microbial and sensory quality of this cook/chilled product.

• Applied Biological Chemistry
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• v.44 no.2
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• pp.81-87
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• 2001

Oyster jeot-gal were prepared in the form of salt-fermented oyster and oyster in soy sauce tentatively and used for investigation the retarding effect of its fermentation in a vacuum from the physicochemical and microbiological points of view. $_PH$ value decreased slightly but amino-N (AN) and volatile basic nitrogen (VBN) increased inversely during the fermentation periods. AN contents were greater in vacuum fermentation than in non-vacuum, whereas VBN were greater in non-vacuum. Total viable cell counts were similar to trend of gentle decrement after increment to some degree but showed higher in non vacuum than in vacuum. In vacuum product, total amino acid contents increased with the elapse of fermentation days or in time of reduction those were higher than in non-vacuum. On the results of chemical analysis, it showed that fermentation was delayed in vacuum and that vacuum fermentation was effective for the shelf-life extension of jeot-gal.

• Journal of Environmental Health Sciences
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• v.27 no.4
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• pp.107-114
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• 2001

The number of covered carts selling snack foods along the streets are increasing in Korea and people enjoy eating foods at these carts. However there are only a few reports on the contamination or sanitary condition of the food carts. This study was performed to investigate the sanitary condition of food and water at the street food carts in the eight major areas of a city. Water and several kinds of food, kimbop(laver rollers) ddeokbokki(stir fried rice cake in hot pepper paste) oemuk(fish cakes) fish cake soup, and soy sauce were collected from four street carts from each of the 8 areas from June to August in 2001 The standard plate counts(SPCs) and coliform groups were examined according to the Food Code of Korea. The nufitness rates of SPCs of the samples were 0~15.6%: 15.6% in kimbop:6.3% in fish cake soup; and 3.1% in water samples SPCs were not detected in some samples. of ddeokbokki, oemuk and soy sauce. The unfitness rates of coliform groups were 0~62.5%; 46.9% in kimbop; 6.3% in ddeokbokki,;22.9% in oemuk 62.5% in fish cake soup; and 3.1% in soy sauce. Coliform groups were not detected in water sample The numbers and unfitness rates of SPCs and coliform groups showed increasing tendencies over time within a day. The higher the air temperature was the more increase of bacteriological growth was observed These results indicate that the level of bacteriological contamination of foods and water in the street carts should be monitored and strict inspection is necessary. There should be legal consequences for serving contaminated food to the public.

• Korean Journal of Food Science and Technology
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• v.2 no.2
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• pp.26-29
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• 1970

Four strains of Sporobolomyces genera were isolated from soy sauce mashes at the fermentating and aging periods and identified. Their salt-resistance and color formation were examined in order to improve the color density and nutrition of red pepper paste preparations. The results obtained were as follows; a) The strain L1, L2, L3 and L4 isolated were identified as Sporobolomyces gracilis, Sporobolomyces roseus, Sporobolomyes gracilis and Sporobolomyces roseus respectively. b) The yeasts isolated were grown on the media containing $0{\sim}10$ percent of sodium chloride but their growth were almost restrained on the media containing $15{\sim}18$ per cent of sodium chloride. And the strain L2 and L3 were more salt-resistant as compared with L1 and L4. c) The strain L3 were the best among the 4 strains of yeasts comparison with their salt-resistance, color and flavour formation.

• Korean Journal of Food Science and Technology
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• v.4 no.3
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• pp.182-186
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• 1972

The possibility of substituting corn or barley for the wheat, one of the raw materials for soy sauce, was studied by measuring the amylase and proteolytic activities of koji. Also optimum conditions of koji making were determined. It was found that substitution of up to 60% of wheat content (of the total bean and wheat content) with corn, yielded good quality of soy sauce. It is also found that barley can substitute 70% of wheat content (35% of the total content).

• Food Science and Preservation
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• v.17 no.6
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• pp.820-825
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• 2010

We investigated changes in the quality characteristics of soy sauce made using salts from deep ocean water; such salts are more economic to obtain than sun-dried salt. pH level and buffer action both decreased as fermentation proceeded. The content of the pure extract after 120 d of fermentation was 7.5%(w/w), and increased as fermentation proceeded. Total and amino acid nitrogen levels after 120 d of fermentation were 1.4% and 0.75%, respectively (both w/w). Of the free amino acids (179.8-315.7 mg%), glutamic acid was the most abundant, followed by alanine, lysine, and leucine. The glutamic acid/total free amino acid ratio was 21.0-23.2%. The content of essential amino acids was 78.0-142.3 mg%; this level increased as fermentation progressed.