• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.386-391
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• 2004

This study was performed to investigate change of quality characteristics on traditional dried Persimmons from Sangju varity regions (sun-dried, Namjang and Bokryong). Moisture contents on drying were decreased and constant at from 7th to 14th days drying periods and its periods were recognized to constructing second peel of dried persimmons. Constructed second peel were affected on quality characteristics of traditional dried Persimmons. Also, in case of semi-dried persimmons were processed at 45∼55% level of moisture content. Final products of semi -dried persimmons were estimated in 25th from initial drying periods. Changes of water activity were increased reducing speed at time of water content decreased, second feel constructing during drying persimmons were introduced to decreasing of water activity. Weights of dried Persimmons were quickly decreased in 21th drying periods and slowly decreased after that time. Weight changing and water evaporation of dried persimmons at the Namjang and Bokryong were slowy decreased and controled after 7∼14th in periods of constructing second feel of dried persimmons. Change of brix in dried persimmons have had in 18∼27% value at initial drying periods and quickly increased after 7∼14th in drying periods and have in high value of 40∼50% at 21th drying periods. At the texture of dried persimmons, hardness were decresed after 7∼14th in periods and effected on decreasing of water content, increasing of drying times. Sensory score of dried persimmons were highest score of color, sweetness and texture at dried persimmons of Namjang. Score of astringency, sourness and mold smell were highest at dried persimmons of Bokryong. Value of highest overall acceptance score was at dried Persimmons of Namjang.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.77-82
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• 2017

The purpose of this study was to evaluate the quality of crackers added with different concentrations (0%, 3%, 5%, 7%, and 10%) of tomato concentrate. The study results found that pH and baking loss rate of crackers of the control were higher than those of the samples. On the other hand, density and moisture of crackers with 10% tomato concentrate were higher than those of the samples. Hunter L values of crackers decreased as concentration of tomato concentrate increased, whereas a and b values of crackers increased. In the texture analysis, hardness of crackers decreased according to concentration of tomato concentrate. DPPH free radical scavenging activity of crackers increased as concentration of tomato concentrate increased. In the sensory evaluation, taste, color, flavor, texture, and overall acceptability of crackers added with 5% tomato concentrate were higher than those of other samples. Therefore, the results suggest that addition of 5% tomato concentrate is effective for increasing consumer acceptability and functionality of crackers.

• Culinary science and hospitality research
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• v.21 no.2
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• pp.187-200
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• 2015

The purpose of this study was to examine the quality of muffins with 0, 3, 6, 9, and 12% kale powder. The specific gravity of muffins prepared by adding kale powder was higher than the control group. The height of the muffins was not significantly different among all sample groups. The weight of muffins with 9% kale powder was higher than other samples. The volume and specific loaf volume of muffins decreased with the addition of kale powder. The baking loss rate of muffins decreased with the addition of kale powder. The moisture content of the samples with kale powder was higher than the control group, whereas pH was lower than the control group. DPPH radical scavenging activity of the control group was 25.70%, but the samples with kale powder ranged from 34.80 to 53.70%. In color, the L value decreased, but the b value increased significantly with the addition of kale powder. The hardness, springiness, cohesiveness, chewiness, and brittleness of the textural properties of the muffins significantly decrease by addiction of kale powder. Sensory evaluation scores in terms of after swallowing, appearance, flavor, taste, texture, and overall preference of groups with 3% and 6% kale powder did not show any significant differences, and the scores were higher than the control group. Based on these results, thus, using less than 6% kale powder would be proper to make muffins.

• Food Science and Preservation
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• v.20 no.2
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• pp.265-271
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• 2013

The objective of this study was to assess the quality characteristics of yanggaeng prepared with different ratios of blueberry powder: 0%, 3%, 6%, and 9%. The moisture content of the control yanggaeng was lower than that of any other blueberry added groups. The pH decreased while the titratable acidity and the Brix increased as the amount of blueberry powder increased. The lightness (L) and yellowness (b) were the highest while the redness (a) was the lowest in the controls. Texture profile analysis showed that the hardness of the added groups were higher than that of the control which were the lowest. The total polyphenol content and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity increased as the amount of blueberry powder increased. The results of consumer acceptance test revealed that the color preference was the highest in the 9% added group while the smell, taste, texture and the overall acceptability showed no significant differences groups. Based on these results, it is suggested that yanggaeng with up to 9% added blueberry powder can be developed as products without adverse effects on sensory characteristics.

• The Korean Journal of Food And Nutrition
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• v.30 no.6
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• pp.1191-1198
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• 2017

This study aimed to evaluate the utilization of the top of a low intake of root, through the analysis of the antioxidant activity of the powder of hydroponic-cultured ginseng. Quality characteristics and antioxidant activity were compared and analyzed with Korea's traditional dessert Gaeseong-Juak, which is made of the powder of hydroponic-cultured ginseng's leaf by adjusting the added volume. DPPH radical scavenging activity of the hydroponic-cultured ginseng by the part powder was in the following order: highly stem, leaf and root. It was measured as 67.9%, 42.9%, and 25.9% at the 1 mg/m level. Gaeseong-Juak was prepared by adding hydroponic-cultured ginseng leaf powder at 0%, 0.3%, 0.6%, and 0.9% of the rice powder. As the content of hydroponic-cultured ginseng leaf powder increased, moisture content, L-value, and a-value were significantly decreased, while the b-value was significantly increased. The texture profile analysis of Gaeseong-Juak was not significantly different among the samples. In the sensory test, the sample containing 0.6% hydroponic-cultured ginseng leaf powder achieved good scores. The DPPH radical scavenging activity of Gaeseong-Juak was significantly increased, as the addition level increased, compared to the original. Based on the above results, hydroponic-cultured ginseng leaf was verified to be a possible natural antioxidant. It can increase food's nutritional values and possibilities when made of hydroponic-cultured ginseng, using leaf which is added to the traditional dessert Gaeseong-Juak.

• The Korean Journal of Food And Nutrition
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• v.33 no.1
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• pp.49-57
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• 2020

The aim of this study was to investigate the antioxidant activities and quality characteristics of jelly added with 0%, 8%, 16%, 24%, and 32% rhubarb stem juice (RSJ). The moisture content and water activity of jelly samples increased significantly with increasing content of RSJ. The pH was highest in control samples; and the more the amount of RSJ added, the lower. Hunter color value of the jelly showed that L was highest in control samples, but it was not significant in RSJ-added samples. The A value was increased significantly with the addition of RSJ. Hardness, gumminess, and chewiness was highest in samples with 0~8% RSJ, and it decreased by increasing RSJ addition. DPPH radical scavenging activity results showed 60% activity in samples with 32% RSJ. ABTS radical scavenging activity was lowest in control samples and samples with 8~32% RSJ showed 70~80% activity, but it was not significant in samples with 8~32% RSJ. The total polyphenol was increased respectively with increasing levels of RSJ. In terms of consumer acceptance, overall acceptability did not show any significant difference among samples, and the color showed the highest value in samples with 32% RSJ and the lowest value in samples with 8% RSJ.

• Korean journal of food and cookery science
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• v.25 no.2
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• pp.170-179
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• 2009

This study examined effects on shelf-life extension and prevention of starch retrogradation in rye-wheat mixed bread (RWMB) samples prepared with substitutions of 20, 40, 60, and 80% rye sourdough (RSD) as well as a control made with the addition of naturally fermented raisin extract. These effects were investigated using mold growth, water activity, and textural characteristics during a storage period of 8 days at $20^{\circ}C$. The activities of the rye sourdough were examined in terms of pH, total titratable acidity, general bacteria, lactic acid bacteria, and yeast counts. As the incubation time of the sour dough increased, pH decreased, while total titratable acidity increased. General bacteria, lactic acid bacteria, and yeast counts increased with increasing incubation time. Mold grew on the external surface of the control group after 6 days and on the surface of the RSD bread samples after 8 days, respectively. With regard to water activity, the control group had increasing activity as the storage period increased. In addition, the 20, 40, 60, and 80% RSD samples had increasing water activities until the 4th day however, these strongly decreased by the 6th day. In terms of textural characteristics, as the storage period increased, hardness increased, while springiness, cohesiveness, and resilience decreased. There were no significant differences in gumminess among the samples. The control, 20, 40, and 60% RSD samples had decreases in chewiness with increasing storage time, however, the 40% RSD sample did not differ significantly during the storage period. Finally, water activity was negatively correlated with hardness (p<0.05). In conclusion, the results indicate that substituting rye sourdough in rye-wheat mixed bread has a prolongation effect on shelf-life, but no effect on the prevention of starch retrogradation.

• Korean journal of food and cookery science
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• v.26 no.3
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• pp.263-271
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• 2010

The purpose of this study was to measure the antioxidant activity of yacon root and to manufacture yacon pickles for commercialization as a functional food. The total phenol content in yacon roots were the highest, 29.96 mg GAE/ 100 g, in the ethyl acetate fraction and the DPPH radical scavenging activity and ABTS radical scavenging activity was 37.07%, and 91.60%, respectively, in the ethyl acetate fraction. The optimum recipe for the pickling solution was determined to be vinegar, water and high fructose corn syrup, at 34%, 22% and 44%, respectively. The quality characteristics of yacon pickles using this solution were monitored during storage at $25^{\circ}C$ for 43 days. The pH value decreased to 2.98 (42 days) during storage and $^{\circ}Brix$ gradually increased during storage. The L-value decreased significantly during storage but there were no significant changes detected in the a and b values. No significant changes were detected in the hardness of the yacon pickles. According to the sensory evaluation, no significant changes in taste, texture and overall acceptance of yacon pickle were observed during storage. These results indicated that yacon was an excellent functional food in terms of its antioxidant activity and that pickling might be a promising methods to maintain the taste and quality of yacon during storage.

• Korean journal of food and cookery science
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• v.29 no.2
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• pp.177-184
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• 2013

This study was conducted to investigate the effects of acorn (fruits of Quercus species) powder on the antioxidant activity and quality characteristics of cookies. Cookies were prepared with different amounts (0, 0.5, 1, 3 and 5% to the flour quantity) of acorn powder. The antioxidant activity was estimated by DPPH free radical scavenging activity and the total phenolic acid content in acorn powder and cookies. For analyzing quality characteristics, bulk density, pH of the dough, spread factor, loss rate, leavening rate, color, texture profile analysis, and sensory evaluations were measured. The moisture contents, a values, total phenolic acid content and DPPH free radical scavenging activity of cookies significantly increased with increasing acorn powder (p<0.001), while the pH of the dough, L values and b values of the cookies significantly decreased with increasing acorn powder (p<0.001). The consumer acceptability score for the 3% acorn cookie groups ranked significantly (p<0.05) higher than the other groups in overall preference, appearance, flavor, taste and color. From these results, we suggest that acorn is a good ingredient for increasing the consumer acceptability and the functionality of cookies.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.2
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• pp.185-192
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• 1987

A green house experiment was conducted to find out the acetylene reducing and $N_2$-fixing activity from photosynthetic and aerobic heterotrophic nitrogen fixing microorganisms in submerged paddy soil under different agricultural locality, soil series, soil texture, soil type, and drainage condition in which samples taken from without nitrogen treatment plot of NPK trials on 16 sites of the farmer's field. The results obtained were summarized as follows: 1. The highest acetylene reducing activity was observed at 7 days after incubation in the light condition (photo synthetic microbes+heterotrophic bacteria) while it was observed at 35 days incubation in the dark condition (heterotrophic bacteria). 2. Among the soil series, photosynthetic nitrogen fixing activity was pronounced more in Jangae, Ogcheon and Hwadong series while lower was obtained in Buyong and Daejeong series. Aerobic heterotrophic nitrogen fixing activity was high in Buyong and Daejong series. 3. Estimated amount of $N_2$-fixation from acetylene reducing activity was equivalented to 3.0 mg in light condition and 4.9 mg/100g/105 days in dark condition. 4. Among the agricultural locality, photosynthetic nitrogen fixing activity was high in rather warm southern part while heterotrophic nitrogen fixing activity was predominated more in mountainous area and Chungcheong continental. 5. Photosynthetic nitrogen fixing activity was predominated in high productive soil while aerobic heterotrophic nitrogen fixing activity was pronounced more in crose coarse sandy soil. 6. The soils properties of high photosynthetic nitrogen fixing activity were constituted of poorly or imperfectly drained clay or clay loam soil while heterotrophic nitrogen fixing activity was pronounced more in well to moderately well drained sandy or sandy loam soil.