• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.905-913
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• 2003

The physicochemical properties of rice flour roasted at various temperatures and times were analyzed, and the quality characteristics of tarakjuk made from these roasted rice flours were investigated. As roasting temperature and time increased, rice flour showed decreasing moisture, protein content, and glucose the major reducing sugar of rice flour. Total amino acid content did not show any significant changes, but the amount of free amino acids and individual amino acids, such as lysine, tryptophane, and tyrosine, decreased. A decrease in L value and increases in a and b values from both roasted rice flour and tarakjuk was observed. Reduced crystallinity and gelatinization temperatures of roasted rice flour were investigated with X-ray diffractogram and DSC, respectively. The thermal transitions between $100.6{\sim}127.6^{\circ}C$ of tarakjuk by DSC are considered to be due to the melting of amylose-lipid complex. As the roasting temperature and time of rice flours increased, tarakjuk showed lower viscosity and higher spreadability. Sensory characteristics, such as nutty flavor, color intensity, and gritty texture increased significantly. Tarakjuk made from rice flour roasted at $185^{\circ}C$ for 25min showed the highest score on overall preference. From the above results, roasted rice flour produced more preferable tarakjuk than nonroasted flour in terms of sensory quality.

• Food Science and Preservation
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• v.22 no.3
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• pp.335-344
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• 2015

The objective of this study was to determine the rheological characteristics and sensory evaluation of yanggaeng by using the functional properties of Momordica charantia. Dried Momordica charantia was roasted at $180^{\circ}C$ to remove its bitter taste. The results of the study were as follows : The phenolic compound of Momordica charantia was $6.30{\pm}0.17mg/g$ in water extracts, which was the highest extractive rate. The anti-oxidant activity of non-roasted and roasted samples was determined in various phenolic concentrations at $50{\sim}200{\mu}g/mL$. The DPPH activities of non-roasted and roasted Momordica charantia water and ethanol extracts were 74.06~92.71% and 86.06~94.07%, respectively. The ABTS were 36.26~98.03% and 67.02~99.60% in water and ethanol extracts, respectively. The anti-oxidant protection factor of water and ethanol extracts were 2.19~2.25 PF and 2.20~2.36 PF respectively, and TBARS were 13.81~40.97% and 23.32~82.47%, respectively. The anti-oxidant activity of ethanol extracts was higher than that of water extracts at low phenolics concentration of $50{\mu}g/mL$, while the roasted sample was higher than the sample that was not roasted. The ${\alpha}$-glucosidase inhibition activity of non-roasted Momordica charantia ethanol extracts was higher than that of water extracts, showing that there were increasing pattern depending on the increases in the phenolics concentration of Momordica charantia. The texture, such as hardness, springiness, cohesiveness, chewiness and color changed in proportion to the concentration of Momordica charantia powder. Moreover sensory characteristics, such as color, flavor, taste, texture and overall acceptability of the non-roasted sample changed in proportion to the concentration of Momordica charantia powder. However, in the roasted sample, the sensory characteristics was improved at a lower concentration (below 1%). Thus, when the yanggang was prepared by Momordica charantia powder as a minor ingredient, it would be desirable to add it after roasting, in consideration of its functional and sensory properties, and at appropriate concentration on below 1%.

• Food Science and Preservation
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• v.11 no.2
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• pp.175-181
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• 2004

As a foundational study for notifing excellence of persimmon leaves tea, the chemical component and antioxidant activity were investigated in persimmon leaves from Dungsi, Gabjubaekmok, Weulhasi and Cheongdobansi and green tea leaves. Total sugar contents in all persimmon leaves more higher than that of green tea leaves, and the highest free sugar contained in persimmon and green tea leaves was sucrose. Free sugars present in persimmon and green tea leaves were composed of sucrose, glucose, fructose, maltose and xylose. Sucrose and fructose took more than 70% of total sugar contents. 31∼32 kinds of amino acid were detected in persimmon leaves and 35 kinds in green tea leaves. And total amino acids contained in persimmon leaves were Dungsi, Gabjubaekmok, Weulhasi and Cheongdobansi, respectively 60.40 nmol/${\mu}$L, 53.21 nmol/${\mu}$L, 52.29 nmol/${\mu}$L and 47.58 nmol/${\mu}$L. Total amino acid contents in green tea leaves was the most abundant of all as 114.72 nmol/${\mu}$L. The contents of vitamin C in persimmon and green tea leaves were in the range of 0.015∼0.089% and 0.01%, respectively. Vitamin C was significant higher content in the persimmon leaves than in green tea leaves. Caffeine was not detected in all persimmon leaves, but the caffeine content of green tea leaves was 6.63 mg/l00 g. The content of catechin was showed in the orders of Cheongdobansi, Gabjubaekmok, Weulhasi, Dungsi and green tea leaves; 0.35%, 0.34%, 0.24%, 0.18% and 0.07%, respectively. The contents of gallic acid in Dungsi and Gabjubaekmok were 0.32% and 0.20%. That of green tea was 1.41%, it was the highest content in all samples. The content of calcium in Chengdobansi was most abundant in all samples as 3516.14 ppm, it was 4∼5 times as that of green tea leaves. Flavor component pattern among persimmon leaves was similar, but that of green tea leaves was different. The IC50(${\mu}$g) value of Dungsi, Weulhasi, Gabjubaekmok, Cheongdobansi and green tea were 64.5, 42.0, 47.0, 64.0 and 19.0 respectively.

• Food Science and Preservation
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• v.18 no.4
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• pp.604-611
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• 2011

Several wild yeasts were isolated from Korean grape varieties before and during spontaneous fermentation. Among them, four strains were isolated based on the alcohol content and flavor production in wine after fermentation of apple juice. In this study, the four yeast strains were identified and characterized. PCR-restriction fragment length polymorphism analysis of ITS I-5.8S-ITS II region with restriction endonuclease Hae III and Hinf I resulted in that all the strains showed a typical pattern of Saccharomyces cerevisiae. Pulse field gel electrophoresis showed three different chromosome patterns with a same band between strains SS89 and SS812. When ITS I-5.8S-ITS II sequences of the four strains were compared with one another, they were similar to those of Saccharomyces cerevisiae CBS 4054 type strain. Identity of the sequences was higher than 97% with those of the type strain. Phylogenetic analysis showed based on the sequences showed they were genetically closed to the type strain. The four identified strains were tested in a medium containing 200 ppm potassium metabisulfite, and the MM10 and WW108 inhibition rates resulted at up to 24 h. The four strains were tested at an incubation temperature of $30^{\circ}C$. The 30% sugar concentration in the medium (w/v) showed the highest growth in 36 h, especially in the case of SS89, which was close to growth 40. The four strains were tested in an 8% ethanol medium (v/v). Alcohol tolerance was initially kept in the incubation process. The strains began to adapt, however, to the exceeded resistance. The four strains showed the lowest inhibition rate at 24 h.

• Food Science and Preservation
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• v.20 no.2
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• pp.191-198
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• 2013

In this study, wheat doenjang was manufactured using Korean wheat meju and soybean meju, and its quality were investigated according to mixing ratio of meju. The general characteristics such as moisture contents, pH and salinity of wheat doenjang, which is fermented and aged at $25^{\circ}C$ for 70 days, were slightly decreased time dependently as similar pattern. The pH of wheat doenjang ranged from 4.95 to 5.11% and generally decreased with aging. The moisture contents was 54.5~57.5%, and there was no significant differences in the aging period. Also, there was no significant changes in the salt contents. The amino-type nitrogen contents were 376.27~600.91 mg% at day 70 of the aging period, and showed 3 fold change compared to the initial contents. The reducing sugar contents showed significant difference between the samples, and repeated fluctuation in the aging period. Wheat meju sample A, which contains 50% of soybean meju, showed the highest antioxidation ability. In addition, wheat meju sample A showed the highest score in the sensory evaluation of the colour, taste, flavor, and overall acceptability. Therefore, wheat doenjang manufacturing at a 1:1 of mixing ratio will lead to desirable quality of wheat doenjang.

• Applied Biological Chemistry
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• v.7
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• pp.92-104
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• 1966

For the purpose of the better dietary management and to empahsize of importance in nutrition education for 552 students at the dormitories, College of Agriculture, Seoul National University, the dietary survey was conducted for each consecutive seven days, from March 7th to 13th at the boy's dormitory, from March 14th to 20th at the girl's dormitory, respectively. In comparison the average caloric and nutrient intake per caput per day at the both, girl's and boy's dormitory with the recommended dietary allowances for age of 25, the intake of calories and all nutrients except riboflavin were over the allowances for the boy, while the caloric intake by the girl was considerablly below the allowance. But it is meant that only 150 calories was actually deficient in comparison with the figure of the average energy consumption determined for the girls at the dormitory of the Sook-myung Woman's University, whose pattern of living was quite similar to those of the girls at this college. Except iron and ascorbic acid, all other nutrients were deficient for the girls. The calories in the form of protein of a diet taken by the boy was 12.9% and that by the girl was 12.8%. Protein quality of the diet taken by boy scored 70 while that by the girl scored 79. NDp Cal% of the diet taken by the boy was 7 and that by the girl was figured out to be 8. Therefore, calculated reference protein taken by the boy was 55.8 grams and that by the girl was 36.9%. Though it is generally recommended that at least 1/3 of the protein should come from animal sources, it was apparent by this survey that providing 1/5 of the protein from animal sources with remaining part of high quality vegetable protein foods in the adequate mixed diet would give satisfactory results for both girl and boy students. This was clearly demonstrated by the recommended reference protein and NDp Cal% met. Significant difference between boys and girls in the average consumption of seasonings was found. In consumption per day of seasonings, boy used 1.5 grams of red pepper powder which means they used 15 times more of red pepper than girls did. Kochujang was used 13 grams by boy-students which was as high as 21 times of that of the girl. Total salt intake by the boy was 34 grams while the girl consummed 23 grams. It is obviously recognized that boys prefer more peppery and salty flavor than girls do. To reduce the amount of protein consummed and to improve the quality of protein food, increase of riboflavin rich food and increase of fat intake in place of grain intake are recommendable to the boy. For the girl's diet, consumption of grains, particularly more intake of barley mal· be recommendable to meet the B group of vitamins allowances as well as the caloric allowance. The use of more servings of yellow green vegetables is needed to the girl.