• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.97-104
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• 2004

Effects of sub-materials such as, ethanol, mustard, and chitosan, on enzymatic, microbial and physicochemical characteristics of kochujang were investigated during fermentation. Activity of ${\alpha}$-amylase was low in chitosan-added kochujang, whereas those of ${\beta}$-amylase and pretense did not show any remarkable difference. Viable cells of yeast and bacteria decreased in sub-material-added kochujang during fermentation, with yeast counts decreasing more rapidly in ethanol- and mustard-added kochujang than that with chitosan. Consistency of kochujang decreased during fermentation, with the highest consistency observed in ethanol-added kochujang. Oxidation-reduction potential was low in chitosan-added kochujang. Water activity of all kochujang groups decreased during fermentation with the lowest in ethanol-added kochujang. Hunter L-, a-, and b-values of chitosan-added kochujang were higher than other groups, whereas increase in total color difference of low-salt without sub-material group was lowest pH of kochujang was the highest in ethanol-added kochujang, whereas titratable acidity increased remarkably in chitosan-added group. Total sugar and reducing sugar contents of kochujang were high in ethanol-and mustard-added groups, whereas ethanol production decreased remarkably in mustard-added kochujang. Amino nitrogen content was highest in low-salt without sub-material kochujang during late aging period. Ammonia nitrogen content was lower in mustard-added kochujang. After 12 weeks of fermentation, ethanol-added kochujang was more acceptable than mustard-and chitosan-added groups in taste, color, and overall acceptabilities.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.287-294
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• 2007

Effect of combined use of anti-microbial materials, such as ethanol, mustard and chitosan, on the quality of low salted kochujang was investigated during fermentation at $20^{\circ}C$ for 12 weeks. Viable cells of yeast increased remarkably during fermentation, but increasing ratio was significantly low in ethanol-mustard added kochujang. Activity of ${\beta}-amylase$ was high in anti-microbial material added kochujang, whereas ${\alpha}-amylase$ and protease activities were low in those groups. Water activity decreased during fermentation with being low in the control kochujang prepared with normal-salt without anti-microbial materials. Hunter L-, a- and b-values of kochujang increased during fermentation, and the degree of increase in total color difference $({\Delta}E)$ was low in ethanol added kochujang. Titratable acidity of kochujang was decreased in anti-microbial materials added group at late aging period, and oxidation-reduction potential was low in the control kochujang. Total sugar and reducing sugar contents of kochujang were high in ethanol-mustard added kochujang. Ethanol contents of kochujang increased at late aging period, with high values in ethanol-chitosan added kochujang. Amino nitrogen content increased during middle of fermentation, and ammonia nitrogen content of kochujang decreased in ethanol-mustard-chitosan added group during fermentation. After 12 weeks fermentation, sensory results showed that ethanol or ethanol-mustard added kochujang were the highest in color and flavor with the highest overall acceptability.

• Applied Biological Chemistry
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• v.51 no.4
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• pp.281-287
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• 2008

Effect of combined use of anti-microbial materials, such as alcohol, mustard and chitosan, or pasteurization on the quality of low salted kochujang was investigated during storage at $30^{\circ}C$ for 12 weeks. Activity of amylase decreased during storage, with lower activity in pasteurized kochujang than the other groups. Acidic protease activity increased during storage, but neutral protease activity decreased after 4 weeks. Viable cells of yeast increased during storage, but bacterial counts decreased gradually and did not show any remarkable difference among the test groups. Hunter a-values decreased as storage time increased, whereas L- and b-values decreased after 4 weeks and the degree of increase in total color difference (${\Delta}E$) was low in the supplementary ingredients added kochujang. The moisture contents and water activities decreased during storage with being lower in supplementary ingredients added groups. Titratable acidity of kochujang was decreased after 4 weeks of storage with the highest in combination of the supplementary ingredients added group. Oxidation-reduction potential was low in the supplementary ingredients added kochujang. Total sugar and reducing sugar contents of kochujang decreased during storage, with the highest contents in the supplementary ingredients added group. Ethanol content of kochujang increased during storage, whereas ethanol production was reduced in ethanol added one. Amino-nitrogen and ammonia-nitrogen contents decreased during storage with being lower in kochujang prepared with supplementary ingredients. Therefore, supplementary ingredients added kochujang would be effective for extending shelf-life of kochujang.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.109-115
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• 1991

To make kochuzang, mixtures of rice and sake cake were used as a source of starch and a small part of sodium chloride needed was replaced by mixtures of ethanol and garlic. Amylase activity during aging of kochuzang was increased in proportion to the ratio of sake cake to rice. Protease activity reached a maximum in the sample replaced 25% of rice with sake cake. The counts of aerobic bacteria and molds were decreased according to the increased ratio of sake. Total acidity and the content of alcohol and amino nitrogen were increased during aging of kochuzang, but the change of pH and the content of reducing sugar were small. After 70 days of aging, the taste and flavor of kochuzang was showed to be excellent in the sample replaced 25% of rice by sake cake. Therefore, it may be possible to replace 25% of rice by sake cake.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.449-455
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• 2005

To reduce saft content of kochujang, various combinations of sub-materials such as ethanol mustard and chitosan were added to kochujang, and their effects on microbial characteristics, enzyme activities, and physicochemical characteristics of kochujang were investigated after 12 weeks of fermentation. Activities of ${\beta}$-amylase and pretense were low in ethanol-mustard-chitosan-added kochujang, whereas no significant difference was observed in ${\alpha$-amylase activity among all groups. Number of viable yeast cells decreased remarkably in mustard-added kochujang during late aging period, and anaerobic bacterial counts decreased in sub-material-added groups. Consistency of kochujang increased by addition of sub-materials, and oxidation-reduction potential was low in chitosan-added group. Mustard-chitosan-added kochujang showed lowest increase in total color difference(${\Dalta}E$) and decrease in water activity. PH of kochujang wns highest in mustard-chitosan-added kochujang, resulting in significantly increased titratable acidity. Addition of sub-material increased reducing sugar contents of kochujang, whereas ethanol production was significantly repressed in mustard-chitosan-added kochujang. Amino nitrogen content was Highest in mustard-chitosan-added kochujang during late aging period, whereas ammonia nitrogen content was lower in ethanol-mustard-added kochujang. Results of sensory evaluation indicated ethanol-mustard-added kochujang was more acceptable than other groups in taste and overall acceptability.

• Proceedings of the Korean Nutrition Society Conference
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• 2003.05a
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• pp.230.1-230.1
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• 2003

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.146-154
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• 1985

Low-salted Kochuzang was made by the replacement of a part of NaCl with 4% ethanol as the preservative. Comparative analysis were performed for general components in 7 kinds of low-salted Kochuzang. The activities of ${\alpha}-and{\beta}-amylase$ and protease were high in ripened Kochuzang of low salt concentration in case of addition of alcohol. The changes of total sugar and pH were remarkably decreased when alcohol and salt were added. Total acid contents showed a remarkable increase when alcohol was not added, and in case of salt concentration. Total nitrogen contents were not remarkably changed, but the contents of amino nitrogen and ammonia nitrogen were increased in case of low salt conuntration with alcohol. Reducing sugar contents were increased in case of low salt concentration and alcohol added. Alcohol contents were not remarkably changed in case of addition of alcohol, but when alcohol was not added and low salt concentration they showed a remarkable increase(about 2.2%). A good Kochuzang may be produced by adding 4% alcohol to a low salted one (5.1% content in Kochuzang) in seventy days of the fermentation.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.193-200
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• 1997

In order to manufacture the low salt and functional Kochujang, salt amount was reduced to 6% and chitosan was added to 0.25% to the Kochujang preparation. The contents of ash, moisture, crude fat and crude protein in Kochujang were not affected by the reduced salt concentration and chitosan addition. pH and titratable acidity were not significantly changed by the addition of chitosan. Ethanol content was higher in 6% salt Kochujang tan in 9% salt Kochujang and decreased by the addition of chitosan. Reducing sugar content was lower in 6% salt Kochujang than in 9% salt Kochujang and increased by chitosan addition. $\alpha$-Amylase activity was slightly inhibited by the addition of chitosan, however, $\beta$-amylase, acidic protease and neutral protease activities were not affected. Amino nitrogen and ammonia nitrogen contents were higher in 6% salt Kochujang than in 9% salt Kochujang, but ammonia nitrogen production was significantly decreased by chitosan addition. Also the growth of bacteria and yeasts were slightly inhibited by the addition of chitosan. From the above results we concluded that 0.25% chitosan was the good concentration to prepare the low salt and functional Kochujang.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.2
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• pp.71-79
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• 1988

For the purpose of producing low salt fermented anchovy by accelerated method with a strong proteolytic bacteria, in this study, a strong proteolytic bacterium was isolated from low salt fermented anchovy and its bacteriological characteristics and properties of protease were experimented. The results obtained were as fellows : three proteolytic bacteria, Aeromonas anaerogenes Barillus subtilis and Staphylococcus saprophyticus were isolated from low salt fermented anchovy($4\%\;of\;salt,\;4\%\;of\;KCl,\;0.5\%\;of\;lactic\;acid,\;6\%$of sorbitol and $4\%$ of alcohol extract of red pepper) after 40 days fermentation. Among these strains, which grow best at $30^{\circ}C$, pH 7.0, B. subtilis was found the best proteolytic strain and benefit for industrial use as shown $0.95\;hr^{-1}$ of specific growth rate, $89{\mu}g-Tyr/hr.ml$ of maximum activity after 12 hrs culture in TPY broth. The protease produced by by B. subtilis showed maximum activity at $35^{\circ}C$, pH 7.0, and molecular weight was estimated to be 23,000 by Sephadex G-100 filtration, and it was supposed to be a kind of metal chelator sensitive neutral protease from the results of strong sensitivity against EDTA, o-phenanthroline and metal ions such as $Cu^{2+},\;Ni^{2+},\;Fe^{2+}.Km$ value of that by method of Lineweaver-Burk was determinded to be $0.73\%$ for casein as a substrate.