• Food Science and Preservation
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• v.22 no.5
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• pp.636-643
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• 2015

This study investigated changes in quality and sensory characteristics of soy sauce (Kanjang) with added Astragalus membranaceus (AK) to develop a new soy sauce product with improved sensory characteristics. The pure salinity slowly increased, but AK 10% decreased. The pH was a constant in all samples. The soluble solid content (Brix) increased after 2 months, but AK 10% decreased. With increased addition of Astragalus membranaceus (AM), the optical density increased after 4 months. The amino nitrogen increased in soy sauce with AK 5%. The total free amino acid content gradually increased in soy sauce with AK 5% aged for 6 months. As the addition of AM increased, the crude protein level decreased, but there was no difference between AK 0% and 5%. The sensory tests of AK 5% after 6 months showed higher acceptance. According to the aging period, the acceptability of AK 5% was the best. The results showed that soy sauce with of AK 5% and aged for 6 months exhibits greatly enhanced quality and sensory characteristics. Therefore, it is expected to be used as a natural resources in seasoning area.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.536-539
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• 2002

This study was investigated for the preparation method of meju by three step fermentation. The steamed soybeans were fermented with nisin-producing Lactococcus lactis subsp. lactis IFO12007 to inhibit the growth of odor-producing Bacilli and promote of normal fermentation of meju. The lactie-fermented soybeans were further fermented with Aspergillus oryzae and Bacillus subtilis. The produced meju by this method showed 54%moisture content and pH 7.0, respectively. The three step fermented meju was soaked in 20% (w/v) brine at $25^{\circ}C$ for 90days. After 30 days, the contents of total free amino acids revealed 4,015 mg% which were higher $3{\sim}5$ times than controls. Among the detected free amino acids, the contents of glutamic acid and leucine showed 925 mg% and 380mg%, respectively. Therefore, the new method of producing meju would be an excellent alternative to improve the quality of soybean fermented food, such as doenjang and kanjang.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.1
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• pp.115-122
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• 1989

The mechanisms of aflatoxin $B_1(AFB_1)$ degradation by ammonia and alkaline pH during the storage of Korean soy sauces were studied. In the 0.05%, 0.1% and 0.5% of ammonia solutions, almost all of $AFB_1$(96-100%) was degraded after 2 to 24 hrs of incubation at $30^{\circ}C$. Increased levels of ammonia in both home made soy sauce(HMSS) and commercial soy sauce(CSS) caused slow increases in pH. The pH change was higher in CSS than in HMSS. The degradations of $AFB_1$ were not observed in the samples of HMSS, CSS, distilled water and 20 % of NaCl solution during the storage, however, when the pHs of the samples were adjusted to 10, the toxin was completely removed in all samples. $AFB_1$ was stable at pH 5 and 7 in bath buffer solutions and buffer solutions+0.2% ammonia, however, $AFB_1$ was degraded completely at pHs more than 9. $AFB_1$ was not degraded even at high concentrations of ammonia(0.2-1.0%) when the pH was maintained at 7 in the buffer solution. It indicated that ammonia content in the system was not important but the higher pH was the reason to degrade $AFB_1$. When the pHs of HMSS, CSS, buffersolution and buffer solution + 0.2% ammonia were adjusted to 5 and then reacted with $AFB_1$ for 5 days, the toxin was stable in all samples. However, when the pHs of the samples were adjusted to 7, about 60-70 % of $AFB_1$ was degraded in HMSS and CSS after 5 days of incubation during which the pH was not changed, but $AFB_1$ in the buffer solution and buffer solution + 0.2% ammonia was not degraded at all in the same conditions.