• Microbiology and Biotechnology Letters
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• v.8 no.4
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• pp.247-253
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• 1980

This experiment was carried out to improve the method of koji preparation by using stainless steel frays which were specially designed and covered with lids. To elucidate changes in chemical composition and formation of enzymes during the preparation of koji with glutinous rice for red pepper paste. professes, amylases, reducing sugars, nitrogens, and microbial contaminations were determined and compared with the case of using trays without lids. The results obtained were as follows. 1. The activities of protease and amylases (both liquefying and saccharifying activities) during the koji preparation were found to be higher incase of using the trays with lids than that without lids. 2. The contents of moisture, soluble nitrogen, amino nitrogen, and reducing sugar were also higher in case of using the trays with lids. 3. Contamination by yeasts and bacteria were markedly low in the trays with lids. 4. Temperature of koji was higher in the trays with lids, however the level of moisture loss was 1ower.

• Korean Journal of Agricultural Science
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• v.41 no.2
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• pp.107-112
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• 2014

Coloring agents in food materials plays important roles in the development of attractive products as well as in the functionality of food such as antioxidant or vitamin supplementation. Carrot has been used as an orange coloring agent in the decoration of food but also a major source of vitamin A complex. Though orange has been considered a typical color of carrot, the Rainbow carrot has been developed recently, which exhibit the various colors such as red, pale yellow, purple, orange or their mixtures. After categorization onto 8 groups by their colors, vitamin A complex (${\beta}$-carotene, lycopene and lutein) and soluble sugars (glucose, fructose, and sucrose) have been analyzed in carrots. The ${\beta}$-carotene was abundant in the groups of orange (Group-O) or groups with the orange color (group-OP, and group-YOP). The content of lycopene content was exclusively high in the red color carrot (group-R). The highest lutein contents were observed from the yellow-purple (group-YP) group. Meanwhile, little amounts of lycopene and ${\beta}$-carotene were observed in yellow-purple (group-YP) nor yellow (group-Y) on yellow (group-Y). Among the reducing sugars in 'rainbow carrots', the amount of sucrose was two times higher than those of fructose and glucose. However, the content of glucose, fructose and sucrose as well as the total reducing sugars did not differ between color groups suggesting little variations on their tastes.

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.908-915
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• 2017

This study was performed to determine the effects of different processing methods (AD: drying at $50^{\circ}C$ for 15 h; ADR: roasting after drying; SAD: drying after steaming; SADR: roasting after steaming and drying) on the quality characteristics, total phenolic content, anthocyanin content, DPPH radical scavenging activity, and reducing powder of red radish (Bordeaux and watermelon radish) tea. The pH of red radish tea was the highest with SAD. In terms of the total sugar content, Bordeaux radish tea showed the highest level with AD, ADR, and SAD, and watermelon radish tea showed the highest level with SADR. The a value of Bordeaux radish tea was higher with AD and ADR. The b value of Bordeaux radish tea was increased with steaming and roasting treatment. In terms of measuring the colors of watermelon radish tea, the L value was decreased while the b value was increased with roasting treatment. The total phenolic content, DPPH radical scavenging activity, and reducing powder with ADR and SADR were higher than those in samples prepared by different processing methods. AD and SAD resulted in higher anthocyanin contents than ADR and SADR. In terms of sensory evaluation, the appearance and color were rated higher with AD and SAD, whereas the flavor and taste were ranked higher with ADR and SADR than in the other samples. The results suggest that red radish (Bordeaux and watermelon radish) tea prepared by ADR and SADR processing methods can be utilized as health functional tea material with antioxidant activity.

• Textile Coloration and Finishing
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• v.32 no.4
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• pp.193-198
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• 2020

In this study, the validity of extracts from food waste as biocatalyst for indigo reduction was examined. Dried food wastes such as apple peel and corn waste were water-extracted and freeze-dried. The reducing power of extracts for indigo was evaluated by the oxidation-reduction potential(ORP) measurement of reduction bath and color strength(K/S value) of the fabrics dyed in the indigo reduction bath. Total sugar contents of the apple peel and corn waste extracts were 60.56% and 62.36%, respectively. Antioxidant activity was 64.78% for the extract of apple peel and 7.96% for the extract of corn waste. Indigo reduction took place quickly with both extracts, and maximum color strength was obtained up to 15.91 and 12.11 within 1-3 days, respectively. The oxidation-reduction potential of reduction bath was stabilized in the range of -500 ~ -620 mV according to the kinds of food waste and the extract concentration. At higher concentration of the extracts, reduction power was maintained for longer time and stronger color strength was obtained. Compared to sodium dithionite, the reducing power of the studied extracts was lower, but the reduction stability was superior to it. The studied extracts were effective biocatalyst as biodegradable and safe alternatives to sodium dithionite for indigo reduction.

• Applied Biological Chemistry
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• v.29 no.2
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• pp.130-137
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• 1986

The five fish meal kojis which contained various ratios of barley were prepared and processed to produce six different fish-soy sauces. The chemical compositions including enzyme activities during fermentation were determined and sensory evaluation was done and changes of absorbance during heating process were also measured. The contents of reducing sugar increased until 12 hours, then slightly decreased and maintained constant level after 36 hours during koji making. The contents of total nitrogen were proportional to the amount of fish meal used in koji. The activities of amylase and protease were increased until 48 hours and then were not changed during koji making. The contents of reducing sugar were increased until 50 days and then were not much changed during koji making. The contents of nitrogen and amino nitrogen in sauces were increased gradually during fermentation. The total acid contents of sauces were increased until 70 days, after which it was constant during fermentation. The absorbances of sauces were increased with time during heating process. In sensory test, the fish-soy sauce the ratio of fish meal: barley of which was 10 : 16 received the highest score for flavor of sauce and the conventional soy sauce, for color and taste in a soup test. Fish-soy sauce resulted good quality when the ratio of fish meal to barley was 10 to 13 and 10 to 16.

• Korean Journal of Agricultural Science
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• v.8 no.1
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• pp.117-125
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• 1981

The changes in chemical compositions of chestnuts were tested during processing in order to elucidate the effects of heat treatments such as boiling, steaming and roasting on the flesh compositions. The results obtained were as follows. 1. The chemical compositions of raw chestnuts were: moisture, 59-61%; total sugar, 24-27%; crude fat, 0.3%; crude fiber, 0.6-0.9%; ash, 1.0%; amino nitrogen, 0.3%; vitamin C, 20-22 mg%; and tannin, 40-48%. 2. The moisture contents were increased to 63.8% by the boiling and to 70.27% by the peeling and boiling from 59.41% of raw ones respectively, whereas decreased to 54.11% by the roasting. 3. Contents of crude protein were decreased to 8.04% by the peeling and boiling procedure from 8.72% of raw ones, and those of amino nitrogen also revealed a decreasing tendency by the heat treatments. However, no significant change was observed in crude fat content. 4. Total sugar contents were decreased by the peeling and boiling procedure approximately 3.0%, whereas reducing sugars were increased 2 to 3 times in the all treatments. 5. Vitamin C contents were decreased 72.0 to 78.0 % by the boiling procedure, 64.2% by the steaming, 51. 6% by the roasting as compared with the raw ones. Tannin contents were increased 11.0% by the boiling, and 46.0% by the roasting respectively, whereas decreased 22.0% by the peeling and boiling procedure. 6. The color was changed to brown with different degree, during the boiling, steaming and roasting procedure. The 0.1% solution of alum appeared to be effective in reducing the browning reaction during the heat treatments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.8
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• pp.1219-1225
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• 2015

This study was carried out to compare quality characteristics and physiological activities of Korean traditional wines fermented by addition of puffed sorghum powder. Using a two-step brewing process for fermented wines, pH, acidity, ethanol, color, tannin, ${\alpha}-glucosidase$ activities, antioxidant, and reducing sugar levels as well as sensory evaluation were measured during fermentation at 2-day intervals until day 8. The pH levels of fermented wines ranged from 4.07 to 5.53, and acidity ranged from 0.13 to 0.86. On the last day of fermentation, alcohol contents of control, raw sorghum, steamed sorghum, and 25, 50%, and 100% puffed sorghum were 16.8%, 11.7%, 13.4%, 16.5%, 15.2%, and 16.4%, respectively. The reducing sugar and ${\alpha}-glucosidase$ activities of puffed sorghum fermented wines were relatively higher than those of the control group, whereas those of steamed sorghum were lowest. As puffed sorghum powder content increased, antioxidant activity significantly increased. In the results of the sensory evaluation, overall preference of 50% puffed sorghum fermented wines was highest among the samples. The results of this study show that physiological activity and quality characteristics of fermented wines containing puffed sorghum powder contribute to value added improvement of sorghum processing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1304-1310
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• 2015

The purpose of this study was to investigate antioxidant activity of yanggaeng containing herbal medicine extracts (YH) by employing various in vitro antioxidant assays for 1,1-diphenyl-2-picrylhydrazyl free radical scavenging, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) free radical scavenging, and reducing power. We also investigated moisture content, pH, texture profile, and sugar content, and evaluated the sensory characteristics of developed yanggaengs. Moisture content of YH was 41.54%. Sugar contents increased while pH decreased as content of herbal medicine extracts increased. Lightness was not significantly different between YH and control. However, herbal medicine extracts enhanced the redness of yanggaeng. Texture profile analysis showed that gumminess and chewiness of yanggaeng added with herbal medicine extracts decreased compared to control. Herbal medicine extracts enhanced yanggaeng's antioxidant activity, reducing power, and scavenging ability. Herbal medicine extracts enhanced antioxidant properties of yanggaeng and made it easier to swallow.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1843-1847
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• 2013

This study is carried out to sanitize rape (Brassica napus) pollen by gamma irradiation. Rape pollens were treated with 0, 5, 10 and 15 kGy gamma irradiations, and then analyzed for the following: general composition, microbial population, reducing sugar, Hunter color values, TBARS (2-thiobarbituric acid reactive substances) values, and VBN (volatile basic nitrogen). Mold and coliform bacteria were not detected in the samples irradiated at 5 kGy or more. Yeasts and total aerobic bacteria were not detected in the samples irradiated at 10 kGy or more (<$10^2$ CFU/g). Moisture, ash, crude protein, crude fat, carbohydrate, reducing sugar and the contents of volatile basic nitrogen in the irradiated pollen did not show any significant changes by irradiation. Hunter color values, $L^*$, $a^*$ and $b^*$ values were decreased with increment of irradiation dose. TBARS values were increased with an increment of irradiation dose. In conclusion, gamma irradiation at 5 kGy was considered to be an effective treatment to control for mycotoxin producing fungi in rape pollen to minimize changes of general composition and physicochemical properties. Further studies should be investigated to reduce the detrimental effects induced by irradiation.

• Food Science and Preservation
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• v.17 no.4
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• pp.541-546
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• 2010

Wild-garlic (Allium victorialis L.) is a perennial plant found in worldwide and has been considered as a favorite vegetable due to its particular smell and taste. However, the study of biological activity of wild-garlic and the development of processed food are in rudimentary. In this study, we evaluated several biological activities, including antioxidant, antimicrobial, and inhibitory activities against human thrombin, $\alpha$-amylase and $\alpha$-glucosidase, of Ulrung wild-garlic. Analysis of the composition showed that Ulrung wild-garlic is nutritive although it is perishable. The color of fresh juice was stably maintained during 10 days-storage at $4^{\circ}C$, but rapidly discolored by heat treatment at $70^{\circ}C$ for 1 h. During heat treatment, the contents of total sugar and total polyphenol were decreased to 75% and 50%, respectively, and acidity was increased from 0.069% to 0.111%. In a while, the brix, reducing sugar, and total flavonoids showed minor changes. The fresh juice showed strong DPPH scavenging activity, reducing power and antibacterial and antifungal activity, but the heat-treated juice lost the antioxidant and antimicrobial activities. The inhibitory activities against human thrombin and $\alpha$-amylase and $\alpha$-glucosidase was negligible in both fresh juice and heat-treated juice. These results suggested that the antioxidant and antimicrobial components in wild-garlic are heat-liable and volatile. Based on our results, we propose non-heat treatment products for processed wild-garlic, for example, fresh juice-added beverage or fermented liquors using wild-garlic.