• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.311-315
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• 2008

This study compared the quality characteristics of sikhye (a traditional Korean sweet rice drink) samples prepared with $N_2$-circulated low-temperature dry malt (RM) and commercial malts. The amylase activities of the malts and the physiochemical (brix, reducing sugar, turbidity, color) and sensory qualities of the sikhye samples were examined. The results showed that RM had higher ${\alpha}$-amylase and ${\beta}$-amylase activities than the commercial malts. And the sikhye made with RM had higher sugar and reducing sugar contents as compared to the samples made with commercial malts. There were no significant differences in L-values between the groups; however, the RM sikhye showed lower a- and b-values. Finally, the sensory evaluation results indicated that RM sikhye received higher sweetness, color, flavor, and overall acceptability scores than the samples made with commercial malts.

• Korean Journal of Food Science and Technology
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• v.48 no.6
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• pp.548-554
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• 2016

Since some strains of kimchi lactobacilli can curdle milk, they can be used for making yogurt. However, the best Lactobacillus plantarum strains for curdling milk for yogurt are still unknown. In this study, we determined the best L. plantarum strains for curdling milk, and the physicochemical properties of yogurts made using different L. plantarum strains were examined. Three strains of L. plantarum useful for curdling milk were identified (YD2, YD9, YD12). The number of lactobacilli was lower in yogurts made with L. plantarum than in those made with control, and among the L. plantarum strains tested, YD12 had the highest bacterial counts. However, the microbial count reached $6.3{\times}10^8CFU/mL$ after 24-h fermentation in all yogurts. The pH of the yogurts decreased after 12-h fermentation, while the acidity increased. The low pH and high acidity decreased the viscosity in all the three types of yogurts, because the acids disturbed gel formation due to protein denaturation. Sensory evaluation revealed that the YD12 group showed a high percentage of completion similar to the control group. YD2 and YD9 showed a high sourness value and low sweetness value, whereas YD12 yielded optimal values for all the organoleptic characteristics. Therefore, YD12 would be a high quality bacterial strain for use as a yogurt starter culture.

• Journal of the Korean Society of Food Culture
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• v.17 no.5
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• pp.653-662
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• 2002

Korean native Perilla Jangachi (salted and fermented vegetable) is popular and well-known but little study on its composition and most palatable condition has been reported. This study was performed to observe the change in the contents of chemical components and sensory evaluation of Perilla Jangachi which was prepared through two processing. First, as a pretreatment, Perilla leaves were soaked in salt water. The optimal level of salt concentration and soaking time (salt 4%, soaking time 42hours) was determined. Second, soaked Perilla Jangachi was steamed and then fermented in various ingredients like soy sauce, sugar, onion and so on. In this study, Perilla Jangachi was made by 3 levels of steaming time(30 seconds, 60 seconds, 90 seconds) and onion contents (10%, 30%, 50%). The optimal level of onion contents and steaming time was determined with the results of sensory evaluation by response surface methodology and analysis of composition. Sodium contents were decreased as the levels of onion contents were increased. Flavonoids contents weren't increased although contents of onion were increased. But they were influenced on steaming time that as the levels of steaming time were shortened, flavonoids contents were increased. To lengthen the shelf-life of Perilla Jangachi, the activities of enzyme peroxidase - which changes Jangachi's quality bad - by various levels of steaming time were measured. After steaming 50 seconds, peroxidase became inactive. Reducing sugar contents were decreased relying on either increased steaming time and onion contents. While steaming 30 seconds and 10% onion contents, the content of reducing sugar was 0.858% but steaming 90 seconds and 50% onion contents, it became 0.372%. Among the sensory attributes, brownness was increased as onion contents increased and steaming more than 60 seconds. Saltiness, sweetness, perilla flavor were greater relying on decreased onion contents. Toughness was decreased as both the amounts of onion and steaming time were increased. With this results, the most optimal adding level of onion content and steaming time was determined. Steaming 72 seconds and adding onion 27% was established as a optimal condition of Perilla Jangachi.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.508-514
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• 2013

This study was conducted to evaluate the effect of various types of functional brown rice milk porridge, which has been popular as a fast yet nutritional food, to promote rice consumption and to examine the best ratio and recipe. Each sample contained 10, 20, 30, and 40% brown rice compared to non-glutinous rice and sweet rice and were applied to mechanical and sensory tests. The moisture content of both non-glutinous rice and sweet rice porridges increased with increasing brown rice content. The viscosity of non-glutinous rice milk porridge decreased as with increasing brown rice content, whereas the viscosity of sweet rice milk porridge increased with increasing brown rice content. The pH was highest for BRT0 at 6.74 and lowest for BGT0, which is sweet rice porridge with brown rice, at 6.27. The sweetness decreased significantly for both sweet rice and non-glutinous rice porridges with the increase in brown rice content. The brightness of weet rice and non-glutinous rice porridges with brown rice increased significantly (p<0.001) with the increase in brown rice content, while the redness and yellowness of the color increased significantly (p<0.001) with increasing in brown rice content. As a result of analyzing the preference in the milk porridge containing brown rice, BRT30, which is non-glutinous rice milk porridge with brown rice, was most preferred at 5.8 in terms of color, while BRT30 was most preferred at 6.2 in terms of fragrance. All samples containing brown rice powder were highly preferred in terms of taste and the overall preference of sweet rice milk porridge was highest for BRT30 (5.8). The overall preference was highest for BGT30 at 6.1 and the preference was generally higher for the experiment groups prepared with sweet rice as opposed to those prepared with non-glutinous rice. Also, the scores for the sensory test were higher when brown rice was added. Therefore, it was concluded that the milk porridge could quickly and easily be prepared with brown rice instead of non-glutinous rice or sweet rice.

• Journal of Dairy Science and Biotechnology
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• v.34 no.1
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• pp.51-57
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• 2016

In this study, the fermentation and quality characteristics of Greek-style yogurt supplemented with stevia leaf extract during storage were examined. Stevia leaf extract was extracted from dried leaves with hot water and 70% ethanol. The pH decreased significantly in all samples over time during fermentation (p<0.05). In particular, the sharpest decrease was detected in the group in which the hot water extract of stevia was added. Acidity increased significantly over time during fermentation (p<0.05). Lactic acid bacteria counts increased in all samples up to 9 h after the start of fermentation, but decreased after 12 h. The sugar content decreased over time, and there were no major differences between samples. Based on the results of a sensory evaluation, the group treated with stevia extract was rated high in sweetness, but was rated somewhat low in color and flavor. Accordingly, it was rated low in overall acceptability. In a storability experiment, as the days of storage increased, the pH gradually decreased, and acidity showed a tendency to increase. The sugar content showed a tendency to decrease and then increase.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.21-30
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• 2008

In this study, the antioxidant activities of 27 medicinal herbs and plants were measured. The dried medicinal herbs and plants were pulverized and extracted by water, 15% ethanol, and 45% ethanol, respectively at above $80^{circ}C$ for 90 minutes. The original and diluted extracts were tested for their antioxidant activities by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging activity assay. Cornus officinalis (C) and Scutellaria baicalensis (S) were selected to develop rice wines with higher antioxidant activities, based on the result of the 45% ethanol extraction. The rice wine developed using sample showed the highest antioxidant activity as comparing to those of other commercial rice wines. The rice wine samples were analyzed for titratable acidity, pH, $^{\circ}Brix$, reducing sugar content, color (L, a, b), amino-acidity, and ultraviolet absorption. The preferences for color, aroma, and overall acceptability were determined using a 9-point hedonic scale by 150 consumers. The sweetness, sourness, fruitiness, color, and medicinal herb-taste levels of the developed rice wines were also evaluated, using a 9-point just-about-right scale. The mean overall acceptability score of c (5.54) was higher than that of sample S. Based on the results, the sourness and medicinal herb-taste levels of sample s should be modified to higher levels, and the fruitiness of sample S also needs to be adjusted. For a future study, the final compositions of the developed rice wines will be adjusted for product launching based on the preference test data acquired in this study.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.60-64
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• 1997

This study attempted to examine the effect on sensory characteristics and texture of Paeksolgi in various volume of adding sugar and steaming time. The most favorite tendency on the quality was over 15% adding sugar and 20 minute steaming time. Evaluation was conducted through objective evaluation firstly and sensory evaluation secondly. The volume of adding sugar was the significant factors which affected the textual characteristics of Paeksolgi. But steaming time and interaction had not affected. In sensory evaluation on the various steaming time Paeksolgi made by steaming time for 20min and over 15% adding sugar showed the most favorite tendency on the overall quality. This condition corresponded to the high level of hardness, adhesiveness, gumminess in comparison with Rheoner measurement. In summary the most favorite factor was 12 hours of soaking time, 10% adding water, 1% of adding salt, over 15% adding sugar, 20 minutes steaming time.

• The Korean Journal of Food And Nutrition
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• v.14 no.5
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• pp.391-396
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• 2001

Effects of substitution of stevioside and maltitol with sugar on the quality characteristics of pound cake and butter cooky were investigated. Pound cakes increased in baking loss rates and decreased in water contents with substitution of sugar by stevioside and malitol. The yellow values of interior of pound cakes, and the lightness and yellow values of surface of butter cookies significantly decreased with substitution of sugar by stevioside and maltitol. Most of texture parameters such as hardness, chewiness, springiness, cohesiveness and gumminess of pound cakes, and hardness and brittleness of butter cookies also decreased with substitution sugar by stevioside and maltitol. In sensory evaluation, texture and appearances of pound cakes containing stevioside and maltitol were positively different compared to that of sugar control. However, butter cookies containing stevioside and maltitol were negatively different in texture and positively different In appearance compared to that of sugar control. Taste, flavor, sweetness and overall acceptability of pound cakes and butter cookies were not different between sugar and stevioside group. In conclusion, textures and appearances of pound cakes might be improvable without affection on other characteristics, and butter cookies were almost the same as the results of Pound cakes except deterioration of appearance, when sugar were substituted with stevioside and maltitol.

• The Korean Journal of Food And Nutrition
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• v.24 no.2
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• pp.159-165
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• 2011

This study was carried out to investigate the quality characteristics of pear jam containing fresh ginger(G1) and ginger powders; dried ginger powder(G2), freeze-dried ginger powder(G3), and hot-air dried ginger powder(G4). The moisture, crude protein, and crude ash content of the control group were significantly higher than those of the experimental groups (p<0.001, p<0.05, p<0.01). The pH of the dried ginger powder added jam(G2) was the lowest(p<0.05). Texture profile analysis found that the dried ginger powder added jam(G2) had the highest firmness, consistency, cohesiveness, and resistance to flow/viscosity among all samples(p<0.001). Regarding the spread-meter value of the pear jam, the control group (G1) and hot air-dried ginger powder added jam(G4) had the highest values. The dried ginger power added jam(G2) had the lowest value among the samples(p<0.01). Regarding the color values of the pear jam, the control group(G1) had the highest L and b values. Hot-air dried ginger powder added jam(G4), on the other hand, had the lowest(p<0.001). The opposite was true for a value: hot-air dried ginger powder added jam(G4) had the highest. From the sensory evaluation, a positive trend was observed for the appearance of the dried ginger powder added jam(G2)(p<0.001). For sweetness, the dried ginger powder added jam(G2) had the highest value. A positive trend was observed for the overall acceptability of the dried ginger powder-added jam(G2)(p<0.001). Therefore, the dried ginger powder-added sample(G2) seemed to be the most appropriate to make pear jam with high acceptability.

• Journal of Life Science
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• v.20 no.11
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• pp.1691-1696
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• 2010

Neohesperidin is a natural new nutrition sweetener, widely existing in plants of dry citrus peel, which can be derived from extraction. Since the sweetness is 1,300-1,500 times greater than that of sugar, neohesperidin are widely used in fruit juices, wines, beverages, bakeries and pharmaceutical formulations, and are particularly suitable for consumption by diabetic patients. However, the yield of extraction from citrus peel waste is very low. In this study optimal yield conditions were determinedusing response surface methodology (RSM) in order to increase the neohesperidin extraction yield. The critical factors for maximum extraction yield were selected extraction pressure ($x_1$), extraction time ($x_2$), and concentration of ethanol ($x_3$). As a result, the extraction yield was improved when the extracting pressure increased. The extraction yield also increased in a time-dependent manner. When adding ethanol as an assistance solvent to the supercritical carbon dioxide, extraction yield was increased as more ethanol concentration was added. Finally, the extraction yield of neohesperidin was improved to about 162.22% compared to ethanol extraction as a conventional method.