• Korean Journal of Food Science and Technology
• /
• v.26 no.5
• /
• pp.561-566
• /
• 1994

The kinds of kochujang were discriminated by using their organic acid compositions, GC peak areas of volatile concentrates and flavor intensity determined by sensory evaluation. Tested kochujang were 51 kinds of traditional kochujang and 10 kinds of industry-produced kochujang in the market. The traditional kochujang included 20 kinds of Sunchang kochujang prepared with glutinous rice, 11 kinds of Boeun kochujang prepared with barley and 20 kinds of Sachun kochujang prepared with wheat. Boeun kochujang was distinguished from other kinds of traditional and industry-produced kochujang by using canonical discriminant analysis for the compositions of organic acids. Among organic acids, lactic acid was the most contributing variable for the discrimination of various kochujang. Traditional and industry-produced kochujang could be classified into 4 groups by using discriminant analysis for GC peak areas. The peak number 2, 4, 8 and 11 were found to be highly contributing variables for the discrimination of kochujang by using stepwise discriminant analysis. Industry-produced kochujang was discriminated from traditional kochujang by using canonical discriminant analysis for the intensity of 8 kinds of flavor property. The taste 'umami' was found to be the most contributing variable for the discrimination of kochujang.

• Korean Journal of Food Science and Technology
• /
• v.25 no.6
• /
• pp.724-729
• /
• 1993

Quality characteristics of 3 kinds of traditional kochujang were investigated during 6 months of fermentation in order to obtain information for the industrial production of traditional kochujarg. Tested kochujang included Sunchang kochujang prepared with glutinous rice, Boeun kochujang prepared with barley, and Sachun kochujang prepared with wheat. The reducing sugar contents of Sunchang, Boeun, and Sachun kochujang increased up to 30, 90, and 150 days of fermentation, respectively, and then decreased thereafter. Ethanol contents of traditional kochujang increased up to $0.4{\sim}1.2%\;at\;120{\sim}150$ days of fermentation and decreased thereafter. Amino nitrogen content of Sunchang kochujang showed a slight increase during fermentation, however, those of Boeun and Sachun kochujang showed a rapid increase up to 150 days of fermentation. Ammoniacal nitrogen content of 100 g kochujang increased up to $50{\sim}75mg$ at 60 days of fermentation and leveled off thereafter. Capsaicin and capsanthin contents of 100 g kochujang were $15{\sim}18mg\;and\;60{\sim}180mg$ before fermentation and decreased to $12{\sim}14mg$ and $50{\sim}120mg$ at 180 days of fermentation, respectively.

• Korean Journal of Food Science and Technology
• /
• v.26 no.4
• /
• pp.389-392
• /
• 1994

Changes in free amino acids and amino nitrogen of traditional kochujang were investigated during 180 days of fermentation. Tested kochujang included Sunchang kochujang prepared with glutinous rice, Boeun kochujang prepared with barley, and Sachun kochujang prepared with wheat. Amino acids remarkably increased during fermentation were methionine, glutamic acid, isoleucine, leucine and tyrosine. However, regardless of kinds of kochujang major free amino acids were serine, aspartic acid, glutamic acid and proline. Glutamic acid was noted as the most contributing to the savory taste of kochujang in relation to the increasing ratio and content among tree amino acids during fermentaion. The correlation coefficent between totals of free amino acids and the contents of amino nitrogen were relatively high (0.87

• Applied Biological Chemistry
• /
• v.23 no.3
• /
• pp.157-165
• /
• 1980

Kojis were prepared from the different starch raw materials such as glutinous rice, barley rice, wheat flour and sweet potato, and were tested in an effort to reduce production cost and to improve quality of Kochuzang(red pepper paste). During the starting period of Koji preparation, there were less significant changes in pH; however, pH decreased somehow in the case of sweet potato, whereas it increased for the other Kojis. In general, the highest acidity was obtained after 72 hours of Koji preparation. Total nitrogen, soluble nitrogen and amino-nitrogen content increased in order of wheat flour, barley rice, and glutinous rice; Kojis they were markedly produced between 72 and 96 hours of Koji preparation. The maximum amount of reducing sugar was observed between 48 and 72 hours of Koji preparation during this period the reducing sugar content varied widely depending on starch source. Sweet potato Koji produced the highest level of ethyl alcohol content after 72 hours of Koji preparation; for the other Koji the same trends were observed after 24 hours. The starch liquefying activities have reached the highest level after 96 hours and for glutinous rice and barley rice; however, they kept on increasing until 120 hours for wheat flour and sweet potato. Koji Starch liquefying and saccharogenic amylase activities tended to increase in order of sweet potato, glutinous rice, barley rice and wheat flour. Kojis Various protease activities were measu-red during the Koji preparation, and they increased in order of alkali, neutral and acidic protease.

• Applied Biological Chemistry
• /
• v.31 no.4
• /
• pp.387-393
• /
• 1988

Changes in chemical composition, viscosity and color during fermentation of improved Kochoojang from four starch sources (wheat, barley, rice and glutinous rice) were examined. Analyses included measurements of moisture, reducing sugars, amino nitrogen, pH, total acidity, viscosity, color and sensory panel scores for viscosity, color, odor and taste. Changes in chemical composition were similar for all Kochoojang products. Decrease in viscosity was greatest during the first 10 days of fermentation. Hunter tristimulus values decreased gradually during fermentation, and total color difference after 60 days was greatest for rice flour Kochoojang. Sensory evaluation showed that the viscosity of rice flour Kochoojang was less desirable than that of the others. However, no significant differences were found in color, odor and taste of all Kochoojang products. A high negative correlation was observed between Hunter a value and visual preference.

• Applied Biological Chemistry
• /
• v.21 no.1
• /
• pp.16-21
• /
• 1978

In order to determine optimum condition for the Ko-Choo-Jang (red-pepper-paste) processing, chemical analysis, mixed ratio, and sensory teat, resulted as follows. 1. The best nutritional value could be obtained after three hours at $60^{\circ}C$, which proved to be the optimum temperature in koji digestion of starch paste. 2. The component ratio of wheat flour to koji-powder was two to one giving the best digestion. 3. The mixing ratio of salt and red-pepper-powder and flour-koji was determined as 1 : 1.5 : 3 by sensory tests. 4. The highest reducing sugar content appeared in a digested mixture using glutinous rice as a starch source and the reducing sugar increased continuously with decreasing, total sugar content in almost every mixture of starches. 5. As a starch source, glutinous rice powder produced the highest total sugar in the beginning stages, however, after 10 day's curing produced less sugar than rice powder. 6. The order of total nitrogen content in the cured paste was recorded as wheat-flour, rice-powder, corn-powder, glutinous-powder, barley-powder, and sweet potato-starch. 7. Amino-nitrogen was increased with curing and the highest, value was observed in the case of wheat flour. 8. In sensory test, Ko-Choo-Jang made of glutinous rice-powder resulted in the best taste.

• Journal of the Korean Society of Food Culture
• /
• v.29 no.2
• /
• pp.187-194
• /
• 2014

The physicochemical and sensory properties of barley Kochujang added with germinated barley powder were periodically examined during storage at 20 for 40 days. The pH of barley Kochujang added with germinated barley powder increased gradually according to the level of added germinated barley powder, whereas it decreased gradually during storage. On the other hand, acidity showed the opposite relationship with addition level. Salinity of the samples decreased gradually according to the amount of added germinated barley powder. Amino nitrogen content of barley Kochujang increased gradually according to the amount of added germinated barley powder, whereas it increased gradually during storage. L-, a-, and b-values of samples increased gradually according to the amount of added germinated barley powder, whereas they decreased gradually during storage. As a result of the sensory evaluation, barley Kochujang added with 5% germinated barley powder was found to be superior in taste, viscosity, and overall preference. Sensory evaluation revealed that addition of 5% germinated barley powder was optimum for improving Kochujang quality.

• Korean Journal of Agricultural Science
• /
• v.6 no.2
• /
• pp.205-212
• /
• 1979

Red pepper paste were prepared by using various raw materials such as rice, glutinous rice, polished barley, polished wheat and corn powder, and their chemical compositions including reducing sugar, amino-N and ethanol were analyzed during the period of aging in order to elucidate effects of these starchy materials on the compositions and qualities of the products. The results obtained are summarized as follows: 1) Koji of these materials were manufactured respectively by inoculating a strain of Asporyzae and their activities of protease and saccharifying amylase were determined. Wheat koji was found to have the highest level of protease activity among the koji, while glutinous rice koji had the strongest amylase activity. 2) Contents of moisture, crude protein, crude fat, and sodium chloride in the red pepper pastes were not changed significantly, however total sugar content was decreased during the period of aging. 3) After 60 days of aging, the highest amount (160mg%) amino nitrogen was detected in the red pepper paste of polished wheat, but higher levels of reducing sugar and ethanol contents were detected in that of glutinous rice. 4) Amino acids in the products were analyzed after 60 days of aging: a) Total 17 amino acids were detected. b) Free amino acid ratio to total amino acid content was approximately 35 percent in average. c) Free glutamic acid was higher than any other free amino acid In the amount and free ratio, but free methionine was lower. d) Lysine content was relatively high, while histidine and glycine were detected in trace. 5) Sensory tests including color, odor and taste on the products resulted in the highest mark for the red pepper paste of glutinous rice but in the lowest mark for that of corn powder.

• Journal of the East Asian Society of Dietary Life
• /
• v.24 no.1
• /
• pp.92-100
• /
• 2014

In this study, the physicochemical and sensory properties of glutinous rice kochujang added with germinated barley powder were periodically examined during storage at $20^{\circ}C$ for 40 days. The pH level of glutinous rice kochujang added with germinated barley powder increased gradually with a higher amount of germinated barley powder, whereas it gradually decreased during storage. On the other hand, acidity showed the opposite pattern. The salinity of samples decreased gradually with a higher amount of germinated barley powder. The L-, a and b-values of samples increased gradually with a higher amount of germinated barley powder, whereas they decreased gradually during storage. Amino nitrogen content of glutinouse rice kochujang increased gradually with a higher amount of germinated barley powder, whereas they increased gradually during storage. In the sensory evaluation, glutinous rice kochujang added with 5~10% germinated barley powder was superior in color, texture and overall preference. Therefore, addition of 5~10% germinated barley powder was optimum for improving kochujang quality.

• Microbiology and Biotechnology Letters
• /
• v.35 no.2
• /
• pp.173-176
• /
• 2007

The purpose of this study was to improve the palatability of fermented red pepper soybean paste (Kochujang). Five individual models of Kochujang were prepared the following: control, glutinous rice containing 50% (A) and 100% (B) of barley, glutinous rice containing 1.5% (C) and 3.0% (D) of red rice. These Kochujangs were prepared and fermented for 60 days at 30 in a crock, and examined for changes in their physicochemical properties. There were no distinguishable change in their pH, acidity, formol-N content. L (lightness)-, a (redness)- and b (yellowness)-values were decreased rapidly until 20 days of fermentation. After 60 days, the values of L-, a- and b- of A, B Kochujang were increased than those of control, C, D Kochujang. Sensory profiles of color, flayer, taste and overall quality on the final products which fermented for 60 days showed that there were no differences in quality of each models. HMG-Co A reductase inhibitory activities were observed in 1.5% of red rice containing Kochujang.