• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.6
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• pp.834-839
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• 2012

The physicochemical and sensory characteristics of Yakju fermented with different ratios of Taraxacum platycarpum (dandelion) root powder (0, 5, 10, and 15%) were investigated. The pH of Yakju decreased and the total acidity and sugar content increased according to the addition of dandelion root powder. Dandelion root powder (15%) showed significantly higher reducing sugar content on the 3rd day of fermentation compared with other groups, including the control. Also, further exposure of fermentation time showed a declining pattern of reducing sugar content. Including control, the alcohol content increased in all Yakju samples fermented with dandelion root powder as fermentation progressed. The Yakju fermented with 5% dandelion root powder showed the highest sensory scores for color, aroma, taste, swallowing, and overall acceptability as $6.38{\pm}1.27$, $5.58{\pm}1.02$, $5.79{\pm}0.98$, $6.08{\pm}1.21$, and $5.96{\pm}0.91$, respectively. In the present study for the production of Yakju, 5% dandelion root powder was the most appropriate amount to be added for the production of Yakju. The result obtained here may provide fundamental data for the traditional Yakju industry, which is interested in using a variety of natural resources.

• Korean Journal of Food Science and Technology
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• v.7 no.4
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• pp.194-199
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• 1975

The physiological and chemical investigations to explain the after-ripening processes in got green pepper fruit were carried out by treating the fruit with ethephon either alone or with phenylalanine. The studied metabolic changes in fruit during after-ripening period was carbon dioxide and oxygen concentration in interior of the pepper fruit, total carotenoid, ${\beta}-carotene$, total sugar, and free reducing sugar in pepper fruit. These metabolic changes were explained inrelation to the color enhancement judged by the color score to explain the after-ripening processes. Ethephon treatment at 500 ppm significantly accelerated color enhancement as compared to the control and further ethephon treatment increased the number by 20 percent which was not possible in control during same after-ripening period. The oxygen concentration in interior of the pepper fruit during after-ripening period was increased in control when the color score (color enhancement) increased rapidly. However, with ethephon treatment, the oxygen concentration was decreased when the color score increased. Although total and free reducing sugar content were decreased during the after-ripening period total carotenoid and ${\beta}-carotene$ content was increased by 50 and 200 percent, respectively, over control. Also the capsaicin contents was increased by 20 percent by ethephon treatment over control. Although phenylalanine treatment did not affect the capsaicin content, capsaicin content tended to be increased by phenylalanine treatment when treated with ethephon. Acknowledgements: This work was supported by funds from Korean Traders Scholarship Foundation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.3
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• pp.317-322
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• 1993

The diffusion phenomena of water, solid and reducing sugar in Chinese cabbage during salting (5$0^{\circ}C$, 25% salt solution) and desalting (5$0^{\circ}C$, distilled water) were investigated. Water loss and solid gain during salting were rapid in the first 6hrs and then almost leveled off. After 24hrs of salting, water loss and solid gain in 100g of initial wet Chinese cabbage were 33.35g and 6.26g respectively. Moisture content was changed from 94.29% to 83.11% during 24hrs of salting. The reducing sugar concentration was also changed from 29.2 mg/$m\ell$ to 6.5mg/$m\ell$, which was linearized as a function of the square root of salting time and showing that Y=30.1841-5.0269√t. After 24hrs salting, water gain and solid loss during desalting were rapid in the first 4hrs and then increased linearly. After 12hrs of desalting, the water gain and solid loss in 100g of initial wet Chinese cabbage were 20.82g and 9.14g respectively. The amount of solid loss after 12hrs desalting was higher than that of solid gain after 24hrs salting due to the diffusion of solute presented initially in the Chinese cabbage during salting and desalting. The concentration of salt in Chinese cabbage after 12hrs desalting was 2.98% which was a suitable salt concentration for the preparation of Kimchi. At this time, the concentration of reducing sugar was only 1.6mg/$m\ell$. The linear regression equation of reducing sugar concentration during desalting was Y=6.7854-1.5992√t.

• Horticultural Science & Technology
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• v.29 no.2
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• pp.144-150
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• 2011

This study was conducted to investigate the nutrient components and physicochemical properties of general ('Superior') and colored potato. Proximate composition, reducing sugar, free sugars, free amino acids, organic acids, minerals were analyzed, and Hunter color values were measured in the study. 'Rose' and 'Blue' (colored potatoes) contained high levels of reducing sugar, and total free sugar content was greatly different according to varieties. Glutamic acid, arginine and ${\gamma}$-aminobutyric acid were detected to be the three major amino acids in colored potato, and the major organic acids of general potato were oxalic acid, tartaric acid, malic acid and citric acid. All potato contained high level of potassium, calcium and magnesium. The Hunter 'L' value was the highest in 'Jaseo'; Hunter 'a' value was high in 'Blue' and 'Jasim'; Hunter 'b' value was the highest in 'Haryoung'. Overall, colored potato had higher amount of nutrients and physicochemical properties than 'Superior'. Therefore, colored potatoes are expected to be highly valuable items for the development and applications of a functional food. In addition, these results will provide fundamental data for improving sitological value, breeding of new cultivar and promoting of roughage usage.

• Journal of the Korean Wood Science and Technology
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• v.47 no.2
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• pp.145-162
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• 2019

This study aimed to increase the sugar and ethanol yield from the mengkuang plant biomass through biological and liquid hot water (LHW) pretreatment and their combination. The results showed that biological pretreatments with 5% inoculum of the fungus Trametes versicolor resulted in the highest alpha cellulose content incubated for 30 days, and 10% inoculum resulted in the lowest lignin content. LHW pretreatment decreased the hemicellulose content of pulps from 10.17% to 9.99%. T. versicolor altered the structure of the mengkuang pulp by degrading the lignin and lignocellulose matrix. The resulting delignification and cellulose degradation facilitate the hydrolysis of cellulose into sugars. The alpha cellulose content after biological-LHW pretreatment was higher (78.99%) compared to LHW-biological pretreatment (76.85%). Scanning electron microscopy analysis showed that biological-LHW combinated treatment degrades the cell wall structures. The ethanol yield for biological-LHW pretreated sample was observed 43.86% (13.11 g/L ethanol by weight of the substrate, which is much higher than that of LHW-biological pretreatment (34.02%; 9.097 g/L). The highest reducing sugar content about 45.10% was observed with a resulting ethanol content of 15.5 g/L at LHW pretreatment temperature of $180^{\circ}C$ for 30 min.

• Journal of the Korean Society of Food Culture
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• v.26 no.1
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• pp.72-79
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• 2011

The purpose of this study was to investigate the fermentation characteristics of Yakju using fresh sprouts from common buckwheat, a Daisan cultivar, and a tartary buckwheat Daikwan 3-3 cultivar to develop a functional Yakju, which is a traditional Korean liquor. As fermentation time increased, alcohol concentration and total sugar content (expressed as Brix degrees) increased, whereas reducing sugar content decreased. In particular, alcohol formation capability was maximized from the fourth to the seventh days of the second mashing stage during the fermentation procedure, which corresponded to the abrupt rise in mashing body temperature. The pH increased slightly when the titratable acidity was kept from increasing as fermentation proceeded. Quercetin and rutin were not present in the control group but their presence in Yakju with added buckwheat sprouts continuously increased with an increase in the fermentation period. Quercetin and rutin contents were higher in the Yakju with added Daikwan3-3 buckwheat sprouts than Yakju with added Daisan buckwheat sprouts. In conclusion, adding buckwheat sprouts improved Yakju quality during fermentation. Particularly, Yakju with added Daikwan3-3 buckwheat sprouts had superior fermentation characteristics and quality.

• Korean journal of food and cookery science
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• v.25 no.2
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• pp.219-226
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• 2009

Red ginseng extract was added to Yanggaeng to determine a practical use for the herb which has medical usage and functionality. We examined the antioxidant activity and quality characteristics of Yanggaeng prepared with different amounts (as ratios of 1%, 2%, 3% to the total materials) of red ginseng extract, as well as those of commercial red ginseng Yanggaeng. The antioxidant activity of the Yanggaengs samples was estimated by the DPPH free radical scavenging activity, $ABTS^{+\cdot}$ scavenging activity, and reducing power. The antioxidant activity of the Yanggaeng increased as a result of the addition of the red ginseng extract. Levels of polyphenol compounds and flavonoids increased according to the extract concentration. The quality characteristics of the red ginseng Yanggaeng were estimated in terms of pH, sugar content, viscosity, color, texture profile analysis, and sensory evaluations. With increasing concentrations of the extract, viscosity and sugar content increased, but pH decreased. In terms of the overall palatability, color, taste, flavor, and hardness, the 3% red ginseng Yanggaeng was determined as the best among the tested samples. Also, the 3% red ginseng Yanggaeng had higher scores than the commercial red ginseng Yanggaeng.

• Korean journal of food and cookery science
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• v.12 no.1
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• pp.60-73
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• 1996

This study was undertaken to investigate the effect of cereals on the physicochemical and sensory characteristics of Noti. Noti is one of Korean traditional pan-fried glutinous cereal cakes. Noti made from the steamed glutinous rice flour, glutinous Chinese millet flour, glutinous millet flour or glutinous Indian millet flour is saccharified with malt, and then pan-fried. Noti also has sweet taste without sugar added. In addition, Noti has elastic characteristic, high calorie and good flavor. Long storage makes it better taste. In this case, Noti was made from the steamed glutinous rice flour. By the sensory evaluation, color, flavor and moistness were unfavorable according to the storage. Consistency was not strongly increased when comparing with the common rice cake depending upon the storage. The texture tended to increase by storage period. Optimum conditions of the safe storage and overall acceptability were to add 15% malt and keep 6hr saccharification time at 60$^{\circ}C$. During the period of storage for 90 days, reducing sugar content was similar, moisture content was low and maintained, and the acid value was not increased abruptly. The hardness was not increased rapidly and fungal growth was considerably low. Cohesiveness and elasticity were increased during storage.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.116-125
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• 2014

This study was performed to evaluate the antioxidant activities as well as quality and sensory characteristics of Rubus coreanus wine sauce prepared with different amounts of Rehmannia Radix Preparata concentrate (RPC, 0, 0.5, 1.0, 1.5 %). Moisture content, salinity and acidity of control were 83.84%, 0.57% and 0.10%, respectively. Sugar content of control was 15.6 $^{\circ}Brix$. Acidities, and reducing sugar contents of sauces increased according to the added amount of RPC, whereas pH and color values of lightness, redness and yellowness in the Hunter color system of sauces decreased. Viscosity of sauces added with RPC significantly increased, compared to that of control. Total phenol contents of sauces increased according to RPC amount. Antioxidant activities such as DPPH and hydroxyl radical scavenging activities improved according to the amount of RPC, due to the increased amount of total phenol contents. Sensory results showed that the overall-preference scores were highest in sauces containing 0.1% RPC. Based on these results, it was suggested that 1.0% RPC addition to sauce is the most suitable to improve quality.

• Journal of the Korean Society of Tobacco Science
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• v.7 no.2
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• pp.129-139
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• 1985

cent was carried out to study on the effect of temperature and humidity to chemical tobacco leaves during the yellowing stage. The results were follows : In the condition of high humidity and low temperature, yellowing time was delayed ; leaf color appeared lack clearness. In the higher temperature and the lower humidity during the yellowing stage : total sugar, reducing sugar and malic acid content were increased. Decomposition of nitrogenous components elevated in $38^{\circ}C$, 85%RH. Changes of total nitrogen content correlated with total curing time. Adecrease of linolenic acid with a corresponding increase of chlorogenic acid proceeded in the condition of low temperature and high humidity. In a view of tobacco quality by chemical components, the low temperature and high humidity during the yellowing stage decreased quality of tobacco leaves. It is considered to control of the proper condition of temperature and humidity during the yellowing.