• Journal of Life Science
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• v.23 no.4
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• pp.529-536
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• 2013

This study was carried out to investigate the characteristics of white soybean Chungkookjang fermented by Bacillus subtilis D7. The highest germination rate was obtained under $25^{\circ}C$ when water was supplied for 4 days at intervals of 2 hr. The total isoflavone content was 971.3 ${\mu}g/g$ before germination and 1023.8 ${\mu}g/g$ after germination. The amino type- and ammonia type-nitrogen contents of Chungkookjang were proportional to the fermentation time. The pH values of all Chungkookjang soybeans increased up to pH 7.8-8.0 during fermentation. The number of viable cells in all Chungkookjang soybeans increased significantly up to 24 hr. The protease activity of all Chungkookjang soybeans increased up to 30-36 hr. The ${\alpha}$- and ${\beta}$-amylase activities of Chungkookjang fermented by B. subtilis D7 were enhanced with increasing fermentation time. Analysis of the effect of Chungkookjang intake on the liver function of mouse showed that the alkaline phosphatase (ALP) activity and the superoxide dismutase (SOD) activity in the Chungkookjang diet group were markedly higher than those in the control group. The asparatate aminotransferase (AST) activity in the germinated soybean Chungkookjang diet group was higher than that in the nongerminated soybean Chungkookjang diet group. Therefore, Chungkookjang soybeans fermented with B. subtilis D7 can be expected to have an increased content of functional components and improved quality characteristics.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.272-279
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• 2003

To determine optimal fermentation period of wild vegetables mixed with black sugar without microorganisms during plant extract fermentation food processing, changes in chemical components, quality characteristics of the fermented broth, and physiological functionality during fermentation period were investigated. pH and $^{\circ}Bx$ of fermented broths decreased gradually during fermentation period. Except persimmon leaf, viscosity of fermented broths of wild vegetables decreased after 3 months fermentation period. Amylase activity increased to $167{\sim}800%$ of its initial level after 6 months fermentation period, and invertase activity decreased by $60{\sim}170$ units after 1 month fermentation. No significant level of cellulase activity was observed. In the sensory evaluation test, inherent flavors and tastes of the wild vegetable decreased during the fermentation period, while those of others gradually increased. Overall acceptability was the highest after 3 months fermentation. Content of total phenolic compounds and electron-donating ability were highest after 3 to 4 months fermentation period, and decreased thereafter. Except Mugwort, tyrosinase inhibitory activity was found in all fermented broths. SOD-like activities were $23.0{\sim}25.1$ and $27.0{\sim}29.2%$ in fermentation broths of acacia flower and persimmon leaf, respectively, and were maintained throughout the fermentation period. Based on these results, fermentation period of 3 to 4 months was determined to be appropriate for plant extract fermentation food processing.

• Journal of Ginseng Research
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• v.5 no.2
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• pp.99-107
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• 1981

Physical, chemical and microbiological changes were periodically studied during six-month storage of fresh ginseng under N2, CO2 gas or subatmospheric pressure condition. The results were summarized as follows. 1. The moisture contents of fresh ginseng gradually decreased during the first 2-month storage and thereafter generally reached at equillibrium. 2. There was no significant change in the reducing sugar content in 1-month storage, followed by$.$a decrease in between 2-and 3-month storage. Thereafter, the reducing sugar content increased at the end of 4-month storage. 3. The total sugar content increased significantly during the first 3-month storage. Under CO2 and Nr gas storage, the total sugar content gradually decreased after 3-month storage, while no significant change was observed in the samples stored under subatmospheric Pressure. Amylase activity gradually decreased as storage period increased 4. The content of saponin decreased as storage period increased, but ginsengoide Rf, Rd, Rc and Rb2 increased significantly in 1-month storage. 5. Regardless of storage methods, sprouting of ginseng and growth of microorganisms were inhibited in all samples during the first 4-month storage. However, growth of microorganisms was observed in the rhizome and injured areas of ginseng after 5-month storage in the N2 and CO2 gas atmosphere.

• Mycobiology
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• v.50 no.6
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• pp.408-419
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• 2022

Filamentous fungi that could be classified into Aspergillus flavus/oryzae were isolated from traditionally fermented meju commercially available in Korea. The samples were analyzed for aflatoxin B1 and ochratoxin A contamination by HPLC; however, no toxin was detected. In addition, fungal and bacterial metagenomic sequencing were performed to analyze the microbial distribution in the samples. The results revealed that the distribution and abundance of fungi and bacteria differed considerably depending on the production regions and fermentation conditions of the meju samples. Through morphological analysis, ITS region sequencing, and assessment of the aflatoxin-producing ability, a total of 32 A. flavus/oryzae strains were identified. PCR analysis of six regions with a high mutation frequency in the aflatoxin gene cluster (AGC) revealed a total of six types of AGC breaking point patterns. The A. flavus/oryzae strains did not exhibit the high amylase activity detected in the commercial yellow koji strain (starter mold). However, their peptidase and lipase activities were generally higher than that of the koji isolates. We verified the safety of the traditionally fermented meju samples by analyzing the AGC breaking point pattern and the enzyme activities of A. flavus/oryzae strains isolated from the samples. The isolated strains could possibly be used as starter molds for soybean fermentation.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.11
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• pp.1588-1594
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• 2012

An 8-wk experiment was conducted to evaluate the effect of replacing fish meal (FM) with soy protein isolate (SPI) on the growth, digestive enzyme activity and serum biochemical parameters of juvenile Amur sturgeon (Acipenser schrenckii). SPI was used to replace 0, 25, 50, 62.5, 75, 87.5, 100% of dietary FM and 100% replacement supplemented crystalline amino acid. Healthy sturgeon with an average initial weight of $26.38{\pm}0.24$ g were randomly assigned to 24 aquaria (8 treatments with triplicates each) at an initial stocking density of 11 fish per aquarium and cultured for 8 wks. The results showed that 75.00% or more substitution resulted in a poor weight gain rate, feed conversion ratio and survival rate compared to that of fish fed the control diet (p<0.05), whereas no significant differences were observed between diets of 25.00% to 62.50% substitution. Protease, lipase and amylase activity in foregut, mid-gut and hindgut were significantly (p<0.05) decreased by diets where SPI replacement levels were 62.50% or more. Levels of serum total protein (TP) and globulin decreased significantly from 21.03, 10.34 to 14.05, 5.63 g/L with the increasing dietary SPI (p<0.05), but alkaline phosphatase activity significantly increased (p<0.05). In addition, supplemental crystalline amino acid in the FM absence diet did not improve growth performance, intestine digestive enzyme activities and serum biochemical parameters. In conclusion, the results from this study showed adverse effects of inclusion of SPI in diets on growth performance, feed utilization and serum biochemical parameters in juvenile Amur sturgeon. Based on WGR and replacement ratio presented in this report, a 57.64% replacement level was recommended.

• 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.

• Food Science and Preservation
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• v.13 no.1
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• pp.95-101
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• 2006

Quality characteristics of Cheongbukjangs with $1\~3\%$ desalted and dried sea tangle powder were investigated after fermentation for 48 hr at $40^{\circ}C$. Addition of sea tangle, irrespective of concentration, did not affect pH and slime content of Cheongbukjang. Color L* and a* values were generally decreased with increasing sea tangle concentration. There were no significant differences in total microbe, amino nitrogen content, and protease and amylase activity between control and Cheongbukjangs with up to $2\%$ sea tangle. However, addition of $3\%$ sea tangle resulted in decreased total microbe, amino nitrogen content, and enzyme activity compared with those of control. Fiber content increased with increasing sea tangle concentration and hardness increased by 1.5 times at $2\%$ sea tangle and by 2.6 times at $3\%$ sea tangle compared with that of control. Results for sensory evaluation revealed that addition of $2\%$ sea tangle was the optimum concentration in view of reducing bitter taste and odor, and improving overall acceptability.

• Journal of Life Science
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• v.16 no.1
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• pp.141-147
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• 2006

The effect of traditional Doenjang supplemented with the extracts of herb medicines (refer as DHM) on the taste component and microbial properties was investigated. The DHMs were divided to four group. Fatty acid compositions were similar between DHMs and control as ratio of each fatty acid to total fatty acids. Concentration of total free amino acid from groups II , III and IV was higher than that of control. Major organic acids were phytic acid, lactic acid, and butyric acid. In isoflavone of DHMs, free daidzein and genistein contents were mostly similar among the groups, and groups m and W were slightly higher as compared with control. Viable cell count of DHMs was shown to be $2.5\times10^7\;CFU/ml$, a similar trend of control. Protease activity of DHMs was higher than that of control(67.65 units), but amylase activity between DHMs and control was almost identical Sensory scores of group II and IV were shown to be brighter than those of group I and II, and decreasing off-odor was more effective. In over all eating-quality, group III and IV were evaluated to be favorable as compared with control and the other DHMs because of supplementing the sweet taste of extracts to Korean indigenous Doenjang.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1079-1085
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• 2013

This study investigated how different amounts of omija fruit (Schisandra chinensis) juice concentrate (0~5%) in sauces affect perceived sensory and quality characteristics. Sauce samples were subjected to chemical analysis for different quality parameters such as Brix, reducing sugars, total phenolic compounds, alpha-amylase inhibition, and alpha-glucosidase inhibition activity. A decrease in pH values was observed with increasing concentrate percentage. As for color, the more concentrate added, the more the L value decreased and other values ($a^*$, $b^*$ and ${\Delta}E$ values) increased. Hypoglycemic effect, as determined by alpha-glucosidase, valuably increased in 4% juice concentrate. As the percentage of concentrate increased, the chemical component values also increased. Significant differences were observed between sauce samples in the sensory evaluation, with the highest overall acceptance being sauce containing 4% juice concentrate. When evaluated with marinated chicken breasts, sauce containing 5% juice concentrate achieved the maximum score.

• Korean journal of food and cookery science
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• v.26 no.3
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• pp.238-245
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• 2010

Sprout vegetable and general vegetable were obtained from radish, red cabbage, vegetable green, buckwheat and broccoli seeds. The vitamin contents had a large deviation, and the vitamin B1 contents decreased and/or was not detected according to the sprouting. This tendency occurred because of the use for growth of sprouts. The mineral contents in sprout vegetables was the highest and was 2~10 times greater than general vegetables. In the growing pathway, potassium was a large consumption nutrient and consumption of sodium was low. $\alpha$-Amylase and total enzyme activities were higher in sprout vegetable than general vegetable, which was also the case of the corresponding freeze dried powders. Sprouting was shown to increase the enzyme activities. Thus, sprout vegetables had several advantages including a rich level of nutrients and safety from agricultural pesticides.