• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.504-510
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• 1988

The physicochemical properties of rice flours which were obtained by dry milling(blade, hammer, test and micro mill) and wet & dry milling (roller & micro mill) were investigated. The resulting flour particle sizes were reduced in the order that of blade, hammer, test, micro and roller & micro mill. Scanning electron microscopic examination showed that the starch granules were freed from the imbedding matrix as the particles became finer. The test-milled flour had the hightest levels of starch damage, maltose value and hot-water soluble amylose content, and the blade-milled flour showed the lowest levels. Amylograph viscosity and gelatinization temperature of the flours decreased as the particles became finer, and the addition of $Hg^{+2}$ increased the peak viscosity of the dry-milled flour pastes, whereas the wet & dry-milled flour did not show any changes. The blue values and ${\lambda}$max values of the iodine complex of the cold-water extractable ${\alpha}-D-glucan$ from flours were in the range of 0.023-0.029 and 518-522nm, respectively, indicating these materials were shown to be mainly composed of amylopectin-like polymer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.6
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• pp.520-528
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• 1987

Quality stability of roasted lavers during heat treatment and storage was investigated measuring the changes in pigments including chlorophyll a, carotenoids and biliproteins, fatty acids and free amino acids as the major quality factors. In roasting of fried lavers, carotenoids were found to lie more stable than chlorophyll a, and biliproteins were most heat labile. The overall heat stability of the pigments depended upon heating time and temperature. Chlorophyll a and carotenoids were retained more than $90\%$ in the casts of roasting for 90 min. at $60^{\circ}C;\;60min.\;at\;80^{\circ}C;\;10\;min.\;at\;100^{\circ}C;\;or\;5min.\;at\;150^{\circ}C$ while biliproteins remained about $70\%$. The lipids of dried lavers including polyunsaturated fatty acids appeared rather heat stable when compared to the stability of pigments under the same conditions of roasting. Spray of sesame oil or seasoning solutions on the surface of lavers after roasting seemed desirable for stabilizing pigments and free amino acids during storage particularly at low water activity. And that was also benefit for the protection of polyenoic fatty acids from rapid progress of oxidation during storage. Free amino acids were reduced fast during roasting, especially most of threonine and glycine while glutamic acid was rapidly lost during the storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1104-1111
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• 2014

To investigate major characteristics affecting the consumer acceptability of Cheonggukjang, the physicochemical characteristics and consumer perception of 16 Cheonggukjang samples (seven commercial samples and nine samples prepared in the laboratory) were analyzed. Overall, consumer acceptability of Cheonggukjang increased with higher contents of amino nitrogen and volatile basic nitrogen, as well as at lower moisture contents. Cheonggukjang samples with higher consumer acceptability showed higher purchase intent (%) and willingness to pay (won/200 gram package), implying consistency in consumer evaluation. Ideal characteristics of Cheonggukjang were lighter color, less water in the soup, stronger characteristic Cheonggukjang taste, sweetness and nutty taste, as well as less off odors, saltiness, and bitterness. The result of this study demonstrates the needs to improve sensory quality by considering the relatively low consumer acceptability of Cheonggukjang samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.792-797
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• 2008

The purpose of this study was to investigate the effects of adding various amounts of ingredients on the physicochemical and sensory characteristics of Bokbunja-jelly. The proximate composition of Bokbunja-jelly was 19.0% for the moisture and 0.8% for the crude protein. The Hunter L-values of Bokbunja-jelly prepared by adding 10 g RME or 120 g sucrose were higher than that of Bokbunja-jelly prepared by adding 20 g RME or 100 g sucrose. The Hunter b-values of Bokbunja-jelly prepared by adding 20 g RME or 120 g sucrose was higher than that of Bokbunja-jelly prepared by adding 10 g RME or 120 g sucrose. The hardness and chewiness were increased with decreasing Rubus coreanus Miquel extracts. According to the results of the sensory evaluation, no significant differences in flavor, sweetness, hardness, elasticity and overall qualities were found. According to the results of physicochemical properties and sensory evaluation, the optimal recipe for preparation of Bokbunja-jelly was determined to be 240 g water, 120 g sugar, 110 g glucose syrup, 4 g agar, 20 g Rubus coreanus Miquel extracts and 0.3 g Rubus coreanus Miquel flavor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.7
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• pp.848-856
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• 2017

This study aimed to investigate the effect of rice nuruk prepared from rice with different degrees of milling (0, 10, 30, 50, and 70%) on physicochemical qualities of yakju. The results indicated significant differences in the qualities of yakju prepared using rice nuruk from rice with different degrees of milling. Specially, pH, amino acidity, brownness, b value, and color difference were significantly reduced as the degrees of milling increased, whereas contents of alcohol and volatile acid, reducing sugar, and L value were increased. Malic acid, succinic acid, and lactic acid were the main organic acids in yakju, and there were significant differences among the treatments in malic acid, lactic acid. However, there was no tendency according to different degrees of milling. In addition, contents of total free amino acids and nitrogen compounds showed no tendency according to degrees of milling, whereas the content of aspartic acid showed a tendency to decrease significantly. The content of 2-phenyl alcohol in the volatile flavor components showed a tendency to increase significantly with higher degree of milling of rice nuruk, whereas contents of n-propanol and iso-amyl alcohol tended to decrease significantly.

• Culinary science and hospitality research
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• v.18 no.4
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• pp.255-265
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• 2012

This study aimed to determine the physicochemical and sensory qualities for yogurt dressing prepared with blueberry juice(0, 10, 15, 20, and 25%). As the amount of added blueberry juice increased, citric acid, malic acid and succinic acid contents increased, but tartaric acid, lactic acid and acetic acid contents decreased. The pH of control group(3.75) was higher than that of the others(3.68-3.48). Sweetness of yogurt dressings decreased as the amount of added blueberry juice increased. DPPH radical scavenging activity of the control group was 26.44%, whereas those of yogurt dressings with blueberry juice ranged from 63.16-87.46%. Color L and b values decreased significantly, whereas a value increased significantly by addition of blueberry juice. Viscosity of the control group was lower than those of the others. The sensory property results showed that yogurt dressing with 20% blueberry juice was rated best. It was also preferred most. These results suggest 20% of blueberry juice is the best substitution ratio for yogurt dressing.

• Culinary science and hospitality research
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• v.17 no.2
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• pp.209-220
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• 2011

This research intends to research on the optimal cooking techniques by adding perilla leaves to raw noodles, in which it has various effects and functions in sterilization. The water content measured in the dough added with raw perilla leaf juice came out high as more perilla leaves were added. More freeze-dried perilla leaf powder decreased water content. The pH of the dough increased significantly as the added ingredients increased with significant differences among the samples. The chromaticity of the dough deliberately decreased in both a and b as the amount of raw perilla leaves in dough increased. The L value of raw noodles with freeze-dried perilla leaves tended to decrease as more ingredients were added. The result of the RVA analysis on the dough with raw perilla leaves showed that the gluten decreased with more raw perilla leaves added. The result of the RVA analysis on the dough with freeze-dried perilla leaf powder indicated that the initial pasting tempo tended to increase significantly with more powder added except for 5% and 7% of powder added with no significant difference. The values dropped as the freeze-dried powder was added Minimum viscosity tended to decrease definitely as more freeze-dried perilla leaf powder was added. The dough's measurement results of WRC showed that water absorbing power of both dough with raw perilla leaves and that with freeze-dried perilla leaf powder reduced significantly as more perilla leaf powder were added.

• Culinary science and hospitality research
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• v.22 no.5
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• pp.179-189
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• 2016

This study investigated the quality characteristics of cookies containing Aronia powder, which is well known for its various functions and biological activity. In this study, we assessed the quality characteristics and antioxidant activity of cookies containing various concentrations (0, 2, 4, 6 and 8%) of Aronia powder(AP). To analyze quality characteristics, pH of dough, moisture content, color(L, a, b), hardness, and sensory properties were measured. Qualities, such as moisture content, redness and yellowness and hardness increased significantly (p<0.001). whereas pH and lightness of the cookies significantly decreased (p<0.001). The antioxidant activity measured by DPPH and ABTS radical scavenging activities were significantly higher than the control, and it proportionally increased as the amount of AP increased (p<0.001). The results of sensory properties showed that cookies made with 2% and 4% AP did not differ significantly from the control in color, taste, and overall quality. Texture scores for the 2% and 4% AP groups ranked significantly higher than those of the other groups. Taken together, the results of this study suggest that AP is a beneficial ingredient for increasing the consumer acceptability and functionality of cookies. The quality characteristics of the 4% added samples exhibited significantly similar or higher values as compared to those of the controls, raising the possibility of developments in health-functional cookies. The results of the sensory evaluation produced very significant values for color, appearance, texture, and overall quality of instrumental analysis.

• Culinary science and hospitality research
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• v.22 no.5
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• pp.95-105
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• 2016

The purpose of this study is to identify the possibility of developing new jelly product with healthy function by the physio-chemical analysis and sensory test of jelly sample groups adding each 20~80% of squeezed Indian spinach liquid. Sugar contents of squeezed Indian spinach liquid was $3.4^{\circ}Brix$. From chromatography, L-value has been decreased by increasing the adding rate of squeezed Indian spinach liquid, and both a-value (redness) and b-value (yellowness) have shown similar trend. According to the measuring result of squeezed Indian spinach liquid the DPPH radical scavenging activity was 15.67 mg/mL, and its total polyphenol contents was 7.00 mg/g. By increasing squeezed Indian spinach liquid, the DPPH radical scavenging activity and total polyphenol contents have shown increasing tendency. Among textures of squeezed Indian spinach liquid, for hardness, sample group of 20% adding was the highest by 4.27%, and for adhesiveness the sample group of 20% adding was the highest by 2.48%, and the lowest was sample group of 80% adding with 0.91%. From the result of sensory test the sample group adding 40% of squeezed Indian spinach liquid has been appraised the most highly in color, scent, sweet taste, chewiness, moistness, and general preference. According to the above results, it is understood that the 40% adding rate of squeezed Indian spinach liquid, when producing jelly, would be the most compatible rate of adding.

• The Korean Journal of Food And Nutrition
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• v.17 no.1
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• pp.1-7
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• 2004

Yoghurt base was prepared from skim milk added with 0.25∼2.0%(w/v) of chlorella extract powder and fermented with lactic acid bacteria(Streptococcus thermophilus : Lactobacillus casei = 1:1) at 37$^{\circ}C$ for 24 hours. Quality characteristics of the yoghurts were evaluated in terms of acid production, number of viable cell, color, texture property, and sensory property during lactic acid fermentation. The addition of 0.25% chlorella extract powder stimulated the growth of lactic acid bacteria which showed the highest number of viable cell counts(l.46${\times}$10$\^$8/ CFU/mL) after 12 hours incubation, and also enhanced the acid production which was pH 4.33 after 12 hours incubation. The L values(brightness) of the yoghurts containing chlorella extract powder were lower than control group, whereas the b values(yellowness) were higher. The hardness and gumminess of the yoghurt added with 0.25% chlorella extract powder were higher than others. Sensory scores of the yoghurt added with 0.25% chlorella extract powder were significantly higher than other groups in color, chlorella odor, sweet taste, chlorella taste, mouth feel, aftertaste and overall acceptability.