• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.56-62
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• 2010

Quality characteristics such as alcohol, acid, and sugar contents of takju brewing mashes prepared using several yeasts were investigated during 12-days of fermentation. Among the yeasts examined, S. cerevisiae led to the highest level of ethanol (10.2-13.4%) and total minor alcohols (0.729-0.831 mg/mL). Regardless of the yeasts used, the acidity showed drastic changes (pH from 3.4-4.2 down to 2.4-2.7) during the first 2 days, and displayed negligible changes from day 4. The total acid contents rapidly increased to the first 4 days of fermentation and leveled off from 4 to the end of fermentation period. The common organic acid components were lactic, succinic and acetic acids. The total and reducing sugar contents varied depending on the yeasts used, with mashes prepared using S. coreanus and S. rouxii producing the maximum total sugar contents (5.43-5.5%) at the end of fermentation. The reducing sugar showed its maximum (7.53-14.89%) at day 2, after which it decreased to its minimum levels (3.04-4.52%). The common free sugar components were glucose and fructose, while S. ellipsoideus led to a higher free sugar level (0.35-5.29%).

• Journal of Ginseng Research
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• v.27 no.2
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• pp.72-77
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• 2003

The six-year old fresh ginseng collected at earlier October was stored for 10 weeks in the condition of 4$^{\circ}C$${\pm}$1$^{\circ}C$ and RH 87∼92%, and the chemical components were investigated in an interval oi one week by taking sample of it after making it to the freeze-dryed ginseng and the red ginseng. The total sugar content of the red ginseng was a little reduced as the period of storage elapsed, and the reducing sugar content was 1.48eic before it was stored and was increased to 23.33% after 10 weeks of storage. For the free sugar of the red ginseng, the content of the fructose was increased, bit the contents of the glucose and the sucrose were gradually decreased after it was a little increased. The content of the maltese was 6.62% before storage and it was gradually decreased. For the free sugar of the freeze-dryed ginseng, the contents of the fructose, the glucose and the sucrose were increased. Especially the content of the sucrose was 10.96% before it was stored and was a increased to 24.38% after 7 weeks of storage, and the content of maltose was not detected. The yield of water extract was a little high at 7-8 weeks of storage and the pH was a little high at 3-4 weeks of storage. The turbidity was not changed for the freeze-dryed ginseng but was decreased for the red ginseng The water non-soluble protein was not detected in the red ginseng, and for the freeze-dryed ginseng the water non-soluble protein was reduced and the water soluble protein was increased as the period of storage was elapsed. The contents of the phenolic compounds for the red ginseng and the freeze-dryed ginseng and have their peak values after 7 and 9 weeks of storage respectively, and the amount of phenolic compounds was larger for the red ginseng. For the content of the non-volatile organic acids, the content of the citric acid was decreased both for the red ginseng and the freeze-dryed ginseng, and the contents of the glut-matic acid and the pyruvic acid were very small for the freeze-dryed ginseng, but were detected in the red ginseng at a maximum value of 37 ${\mu}$g/g and 592 ${\mu}$g/g respectively.

• Korean Journal of Food Science and Technology
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• v.1 no.1
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• pp.51-61
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• 1969

In order to eliminate the considerable loss of rice by insects, to protect the human body from toxin excreted by some microbes, and to promote the storage efficiency of rice by employing the irradiation, the following experiments were carried out. Two varieties of rice, Paldal and Nongkwang polished and unpolished by the conventional methods and were packaged in polyethylene bags. After irradiating to the doses of 6-400 Krad of gamma-radiation from a $Co-^{60}$ source the samples were stored at the room temperature $20^{\circ}C$ for 8 months. The effects of radiation in terms of the removal of insects and microbes and the changes of chemical components (such as moisture, amylose, free sugar, and rancidity) were determined monthly from march to October during the storage. 1) Infestation of insects was greatly influeneed by the packaging materials used. There was no infestation in rice being packaged in a polyethylene bag, while as the rice packaged in a straw sack was infested in two months of the storage. 2) Some yeast and molds survived 400 K rad of radiation. Sterilizing dose to inhibit reproduction and growth of microbes was presumed to be higher than 400 K rad. Yeast mainly were found on the surface of rice, but mold were embeded into rice kernels by mycelium. 3) Changes of moisture contents during storage was not affected by radiation but was by humidity of the storage room. 4) Amylose content in starch increased with increasing dose of radiation and with the length of storage time, indicating possible depolymerization of starch molecules. 5) Free reducing sugar content was not affected by radiation and decreased with storage time. 6) Rancidity also increased with does and storage time.

• Food Science and Preservation
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• v.18 no.6
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• pp.844-852
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• 2011

In this study, various antioxidant propertieswere evaluated by analyzing the proximate composition and free-sugar and DNJ contents of the Bombyx mori L., Mori fructus, Morus ramulus, Mori folium, Dioscoreae rhizome and Inonotus obliquus extracts, and the antidiabetic effect was evaluated through an in-vivo experiment. Product evaluation was conducted after preparing a beverage for the easy use of the mixed extract for biological activity, as a functional resource. The biochemical composition of the extracts was 0.31% crude protein, 0.114 g/100 mL free sugar and 161.02 mg/gdw DNJ, all of which showed excellent results in all the antioxidant ability and ${\alpha}$-glucosidase inhibition ability experiments. The beverage showed the following functionalities. The total-polyphenol content was 71.93%, but the electron-donating ability was highest in the 5% extract concentration. Moreover, when the TBARS values were experimented on, KO2 showed an especially high scavenging ability. During the five-week beverage supply after inducing diabetes with streptozotocin (STZ), the change in the blood sugar was measured, and the STZ-induced diabetes+oral-beverage group (C) showed a lower blood sugar level than the diabetes comparative group (B) in the second week. In the STZ-induced diabetes+free-diet/beverage group (D), the blood glucose level also slowly decreased in the second week. The lowest blood glucose level among the STZ-induced diabetes groups was shown in the fifth week.

• Food Science and Preservation
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• v.9 no.2
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• pp.174-178
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• 2002

Changes in amino acids, organic acids and free sugars of soybean sprouts cultivated with extract of Glycyrrhiza glabra(GGE) during growth of 4 days were investigated. GGE was utilized as sprouting water of soybean and adjusted to 100 ppm, 200 ppm, 300 ppm and 400 ppm. Content of total amino acids of soybean sprouts cultivated with GGE was the most abundant, when soybean sprouts were cultivated for 3 days with 100 ppm of PGE. Content of aspartic acid was increased according to culturing days, but glutamic acid was shown to be a opposite trend. Content of total free sugar of soybean sprouts cultivated with GGE was lower than those of control group, and then increased by increasing of culturing days within GGE groups with same concentration. Sucrose of all groups during growth of soybean sprouts was decreased, but the other sugars were increased. Content of total organic acids was increased by increasing of culturing days and was the most abundant in soybean sprouts cultivated with 200 ppm of GGE among same groups. In conclusion, GGE as sprouting water of soybean was effective to increase of contents of amino acids and organic acids in soybean sprouts, indicating that GGE accelerated the quality of soybean sprouts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.786-790
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• 1996

The changes in chemical constituents of onion in Korea and the degree of hydrolysis in onion by-drolysates by treatment of viscozyme L, celluclast 1.5L, pectinex and cereflo were investigated. Proximate compositions of onion in Korea were as follows; The contents of moisture, protein, lipid, carbohydrate and ash were 89~90%, 1.8~1.9%, 0.4~0.5%, 7.1~8.5% and 0.3~0.5%, respectively. Major free sugars were identified to be glucose, fructose and sucrose and major free amino acids were as cysteine, histidine, arginine and glutamic acid. The degree of hydrolysis by treatment of viscozyme L, celluclast 1.5L, pectinex and cereflo was 69%, 71%, 80% and 62%, respectively. During the enzymatic hydrolysis, free sugar and total sugar content increased however, pyruvic acid content decreased significantly.

• The Korean Journal of Food And Nutrition
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• v.33 no.2
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• pp.117-130
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• 2020

The purpose of this study was to compare differences in the main food components of quinoa (Chenopodium quinoa Willd.) cultivated in Hongcheon after steaming, boiling, and roasting. Among the general components, crude protein, fat, and ash content were the highest in raw quinoa. Dry matter and carbohydrate content was the highest in steamed quinoa, while total dietary fiber content was highest in roasted quinoa. Total amino acid contents were the highest in boiled quinoa and lowest in steamed quinoa. Fatty acid content was highest in raw quinoa and lowest in boiled quinoa. The mineral (calcium, potassium, and phosphorus) and vitamin content was most enriched in raw quinoa, while iron, magnesium, zinc, and manganese were highest in boiled quinoa. For free sugars, the fructose and sucrose levels were highest in raw quinoa, while glucose level was highest in roasted quinoa. The water-soluble vitamin and free sugar contents were lowest in boiled quinoa. In summary, nutritional levels of vitamins vulnerable to heat and unsaturated fatty acids decreased after cooking with heat, while those of amino acids and saturated fatty acids increased after cooking with heat, although there were variables based on different cooking methods.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.665-673
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• 2012

The purpose of this study was to propose optimal mixing proportion by adding stevia in powder form, which are low caloric and high intensity sweetener to cookies, and to determine the characteristic of product. It reduced the average sugar content of cookies to 50%, processed stevia powder, add them in 2, 4, 6, and 8% to make cookies and measured various product characteristics, including anti-oxidant activity. The antioxidant activity was highly correlated with the total phenolic composition of stevia cookies (r=0.967). Total phenolic contents and DPPH free radical scavenging activity of cookies significantly increased with increasing stevia powder. The bulk density of the dough, spread factor and the hardness, total polyphenol contents and DPPH free radical scavenging activity of cookies significantly increased with increasing stevia powder, while the pH of the dough, and L values of the cookies decreased with increasing stevia powder content (p<0.001). Additionally, the consumer acceptability scores for the 4% stevia cookie groups ranked significantly (p<0.001) higher than those of the other groups in color, taste, flavor, sweetness and overall preference. All the take together, the results of this study suggest that stevia powder is a good ingredient for increasing the consumer acceptability and the functionality of cookies.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.1
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• pp.73-79
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• 2016

This study investigated the quality characteristics of burdock glutinous rice dasik prepared with different contents of freezedried burdock powder (0, 3, 6, 9 and 12%) and roasted glutinous rice. The moisture contents of burdock glutinous rice dasik significantly increased as the amount of burdock powder increased(p<0.001). The L-value, a-value and b-value of burdock glutinous rice dasik were lower than those of the control group. The sugar content of glutinous rice dasik added with 6% or more burdock powder was higher than that of the control group. The hardness and adhesiveness significantly increased as the amount of burdock powder increased. The DPPH free radical scavenging activities of burdock glutinous rice dasik added with 9% and 12% burdock powder was higher than that of the control group. In the sensory evaluation, the burdock glutinous rice dasik added with 6% burdock powder was highly preferred, and was thus as the optimal mixing ratio for texture and sensory characteristics.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.2
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• pp.263-271
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• 2011

This study was performed to develop duck stock using various nutritional elements in duck bone by the addition of malic acid (0.5%, 1.0%, 1.5% and 2.0%). Moisture contents, b value, and pH were decreased, while the L value, a value, salinity, and sugar contents were increased by increasing the ratio of malic acid. Thirty four types of free amino acid were detected, and the highest individual amino acid content was 1.0%. In a test for different attributes, malic acid content significantly affected properties including color intensity, transparency, acid flavor, savory flavor, acid taste, and savory taste. In the acceptance test, a malic content of 1.0% was preferred for appearance, taste, and overall quality. The optimal malic acid content for maximizing the overall quality of duck stock was 1.0%.