• 한국미생물·생명공학회지
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• 제17권4호
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• pp.370-378
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• 1989

토양으로부터 역가높은 CGTase를 분비하는 호알칼리성 미생물을 분리하였으며, 동정 결과 Bacillus circulans로 판정되었다. 배양액 중의 CGTase를 ammonium sulfate 침전, DEAE-Sephadex 그리고 Sephadex G-100 column chromatography로 분리, 정제하여 단일 단백질 band를 얻었다. 정제된 CGTase의 분자량은 약 93,000, 최적 pH와 온도는 6.0, $50^{\circ}C$였으며, pH와 온도안정성은 5.5-11, $65^{\circ}C$까지였다. Soluble starch를 기질로 할 때의 $V_{max}$ 와 $K_{m}$ 값은 각각 0.16$\mu$mole $\beta$-CD/min, 14.3mg soluble starch/mi이였고 24시간 반응액의 $\alpha$-：$\beta$-:${\gamma}$-CD 의 생성비율은 1：8.1：1.9로서 $\beta$-CD를 우선적으로 합성하였다. 기질로 glucose와 maltose를 사용하였을 때 CD합성작용이 없었으며, sweet potato 그리고 cornstarch를 사용하였을 때 가장 높은 CD합성작용을 보였다. 어느 수준 이상의 과다한 CGTase 첨가경우에는 $\alpha$-CD생성이 급격히 증가하였다. 또한 정제된 CGTase는 stevioside에로의 당전이성을 갖고 있었다.

• 한국미생물·생명공학회지
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• 제25권2호
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• pp.166-172
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• 1997

Aspergillus niger was selected as a strain producing the potent raw starch hydorlyzing enzyme. These experiments were conducted to investigate the conditions of the glucoa- mylase production, the purification of the enzyme, some characteristics of the purified enzyme and hydrolysis rate on various raw starches such as com, rice, potato, glutinous rice, sweet potato, wheat and barley. The optimum cultural temperature and time for the enzyme production on wheat bran medium were $30^{\circ}C$ and 96hrs, respectively. The respective addition of yeast extract and nutrient broth on wheat bran medium increased slightly the enzyme production. The enzyme was purified by ammonium sulfate fractionation and DEAE-cellulose column chromatography. The specific activity of the purified enzyme was 30.7u/mg-protein and the yield of enzyme activity was 25.8%. The purified enzyme showed a single band on polyacrylamide disc gel electrophoresis and its molecular weight was estimated to be 56,000 by SDS-polyacrylamide disc gel electrophoresis. The isoelectric point for the purified enzyme was pH3.7. The optimum temperature and pH were $65^{\circ}C$ and pH 4.0, respectively. The purified enzyme was stable in the pH range of pH 3.0-9.5 and below $45^{\circ}C$, and its thermal stability was slightly increased by the addition of $Ca^{2+}$. The purified enzyme was activated by $Co^{2+},\;Sr^{2+},\;Mn^{2+},\;Fe^{2+},\;Cu^{2+}$. Raw rice starch, raw corn starch, raw glutinous rice starch, raw sweet potato starch, raw wheat starch and raw barley starch showed more than 90% hydrolysis rate in 48hrs incubation. Even raw potato starch, most difficult to be hydrolyzed, showed 80% hydrolysis rate. The purified enzyme was identified as glucoamylase.

• 동아시아식생활학회지
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• 제9권1호
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• pp.55-63
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• 1999

This research was conducted to estimate waste rates of 69 food items after pre-preparation and amounts of food wastes disposed and it's reduction effect by education in some institutional foodservices for reduction of the food wastes. The result are as follows: 1. The waste rates were 55.40% for sweet corn, 5.73% for potatoes, 19.14% for sweet potatoes, and 33.47% for chestnuts. 2. The waste rates of fruits were 0.21-49.36%. Food items with over 40% waste rate were banana, watermelon, and pineapple. 3. The waste rates of vegetables were 1.14-52.90%. The number of foods with under 10% waste rate were 14 items(red pepper, green pepper, chard, and so on), 10-20% was 9 items(perilla leaf, chinese cabbage, ginger root, and so on), 20-30% was 5 items(root of chinese bellflower, garlic, radish-leaves, burdock, welsh onion-large type), 30-40% was 3 items(shepherd's purse, head lettuce, kale) and over 40% was 3 items(water dropwort, crown daisy, mallow). 4. The waste rates were 24.30% in chicken, 9.53-13.79% in eggs, and 9.30-55.32% in fishes. The waste rates of vegetables and fishes were higher than those of other food groups. 5. There were significantly different in amount of food wastes disposed (g/person/day) to institutional foodservices (hospital＞industrial institution＞ Korean restaurant＞elementary school). The amount of food wastes disposed, especially amount in pre-preparation phase, after education for reduction of food wastes was significantly reduced. Since these study results show significant deviations in food waste rates and education effect, there should be more studies for standard waste rates of each food and systematic education method for reduction of food wastes.

• 한국식품조리과학회지
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• 제19권2호
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• pp.144-154
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• 2003

A survey on meal preferences from 693 middle school students was conducted with the objective to enhance the quality of the school food service in Gwangju and the Chollanamdo area. Data were collected by questionnaires and analysed with the SAS program. The most preferred rice was cooked rice; the most unusual meal preference was laver rice; and the most-liked bread was sweet red bean jam bun. The noodle of choice was Tchajangmyon, and the most-liked rice cake was reasoned bar rice cake. The highest ranted korean soups were boiled fish paste soup, kimchi stew, and short rib sour. The most preferred fried meal included fried beef with sweet and sour sauce, and favorite side-dishes were seasoning vinegar squid and kimchi. Yogurt and strawberry were the preferred desserts. A gender difference in preferred foods was seen. The males tended to favor rice with blackish bean sauce, dumpling soup, beef bean curd soup, beef soup, short rib soup, beef bone and tripe soup, hot shredded beef soup, chopped roast chicken, pork roast, roast meat, steamed pork short-ribs, fried port, fried ham, sausage, milk, and yogurt. Males were partial to staple foods and side dishes, The, females favored laver rice, seasoned bar rice cake, bean sprouts soup, fried squid ring, seasoned cucumber, seasoned bean sprouts, fried kimchi, fruits salad, corn salad and citrus fruits. Females tended to choose lighter meals. Meal preference according to residential area showed that, students in Gwangju had more preferences than students in the Chollanamdo area. Classified according to grades, third graders had the greatest meal preference.

• 한국식품조리과학회지
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• 제15권4호
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• pp.338-352
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• 1999

This research was carried to investigate the food preference of students, from elementary school, middle school, high school, university and industrial workers on Jinju, Sacheon and Jinyang by age and sex. The results were obtained as follows. In case of rice as the stationary food, plain white boiled rice showed the highest preference among all the groups. Most of groups liked most of one-dish meals such as kimbab, fried rice with kimchi, dumplings and bibimbab, especially the elementary school students and middle school students. On the other hand, high percentage of industrial workers disliked the western food such as pizza, hamburger and sphagetti. Most of subjects liked jajangmun, nangmun and bibimgooksu as noodles. As the side dishes generally they prefer the soup to stew. Male prefer the soup with beef and female prefer soup with vegetables. Stew with kimchi and stew with soybean paste showed high preference among most of groups. Most of broil food showed high preference, and students prefer meat to fish as broil cooking materials especially younger students. As a general they liked soybean sprout, spinach and wild sesame leaf as namul cooking method and they liked korean cabbage kimchi, chonggak kimchi, kackdoogi and dongchimi as kimchi. As a dessert subjects liked most of fruits and they liked yoghurt, fruit juice, milk, sikhae and soda as drinks generally. On the other hand snacks such as cooky, candy, cake, corn, rice cake, sweet potato have the lowest percentage preferance as a dessert, but students from elementary schools showed the highest preferance to sweet such as cooky, cake and candy than any other group. These food preferance results showed some nutritional problems especially young age students. They should eat more green-yellow vegetables, liver food and dried small sardine and they should reduce snacks such as candy and cooky and soda drinks. Therefore it is necessary to conduct nutrition education by parents, teachers and dietician together to improve their food habits and their health.

• 미생물학회지
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• 제21권2호
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• pp.51-60
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• 1983

Cultural characteristics of Strptomyces griseolus isolated from the soil were investigated. This strain was disclosed to utilize D-xylose, and D-glactose in preference order as a carbon source with the formation of glucose isomerase. The addition of sweet potato starch also proved effective promoting the total enzyme activity measured at 29% higher than the control. Corn cob, one of waste agricultural resources, was hydrolyzed in 2~3% $H_2SO_4$ solution at $100^{\circ}C$, 3~5 hours to produce a xylose syrup which gave rise to the recovery of 19.9% in a batch system and 28.2% in a repeated system. By the addition of both 2% of xylose syrup(Be'28) prepared by and us 65% of corn steep liquor (total nitrogen 1.2%), enzyme induction was maximized. The enzyme activity was stimulated by the xylose and the cell growth by the C.S.L. Also, remarkable increase of enzyme activity was noticed by the addition of protein acid hydrolysate 86.2% higher than the control. $QO_2$ of the biomass cultured in 30L capacity jarfermentor recorded low oxygen requirement of 251.2 1/hr. Maximum activity of glucose isomerase was observed noted at the 9th hour after inoculation which is 2 hours faster than the stationery was observed noted at the 9th hour after inoculation which is 2 hours faster than the stationery phase of the biomass growth. Glucose isomerase from the strain was activated by adding the $Co^{++}\;and\;Mg^{++}$ with optimum temperature of $73^{\circ}C$ and pH of 7.2. Conversion ratio of 60% glucose to frutose was 42.5% after 70 hours reaction.

• 한국식품영양과학회지
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• 제30권1호
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• pp.152-158
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• 2001

In this study, we determined major foods and food groups which contributed to the intake of folate in korean child-bearing women. Folate content of the major foods was also analyzed. A total of 91 healthy women with childbearing potential participated. They were divided into one of three groups by age; A (15∼24 yrs), B(25∼34 yrs) and C (35∼49 yrs). Food consumption data of the subjects were obtained by the 24-hr recall method. The rate of contribution of each food to the total intake of dietary folate was determined. Seventy major foods for folate were selected from the 178 foods they consumed. Two sets of the 70 foods were collected from different markets. After extracting folates from the foods by heating with a HEPES-CHES buffer, the samples were treated with α-amylase, protease and folate intakes was Korean cabbage kimchi followed by laver, soybean sprout, rice, yolmu kimchi, eggs, lettuce, perilla leaves, sea mustard and radish root. Food items that contributed to folate intake were slightly different among the age groups. Although the folate content of Korean cabbage kimchi was 51.6 ㎍/100g, but due to the high amount of intake, it was ranked the first major food prviding folate. High folate foods containing over 100㎍/100g were laver, corn flakes, spinach, mungbean, sesame, quail's eggs, small radish kimchi, kidney beans, leeks and peanuts. However, based on the serving size, spinach, corn flakes, leeks, sweet potato, pepper leaves, quail's eggs, crown daisy, small radish kimchi and perilla leaves contributed above 50㎍ of folate per serving size.

• 한국식생활문화학회지
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• 제2권1호
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• pp.17-24
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• 1987

As people know how to brew a wine from fruits and cereals, they continued to develope various wines good to their taste. Korean wines are also ones made from cereals and they have long been eager to improve the delicate taste. They used to drink Takju, raw rice wine, made from nonglutinous rice and Nuruk, a kind of yeast starter. During Koryo Dynasty, Soju a liquor was imported from Won(the Chinese dynasty). Nowadays this traditional folk wine, which had been developed variously and drunk all over the country, is decreasing year after year. The purpose of this study was to review on the wines ; its kinds, raw materials, brewing method, manufacturing utensils, measuring units and devices and the terms for wine making based on 20 documents published in 1600, in the middle of Yi dynesty. The results of review were as follows. 1. There were 121 kinds of wines at that time in Korea. 2. Among the raw materials for wines, major materials were glutinous rice, nonglutinous rice, wheat flour, wheat, mung bean, and black soybean. And minor materials were pepper corn, Lycium chinenisis, cinnamon, pine needles, pine nuts, jujube, mugwort leaves, lotus leaves, pine corn, pine bud, chrysanthemum, pine flowers, honey, Acanthopanox seoultenses, bamboo-root, marrowbone of blak cow, sweet flag, Ciprus noblis, Saurea lappa, honey suckle, Tricho santhes, azalea, the leaves of the paper mulberry, and bark of chungum tree. 3. There were several kinds of wines such as a wine without using Nuruk, a wine made from glutinous rice, nonglutinous rice, or glutinous and nonglutinous rice with flour. 4. There were several brewing methods for wines such as a wine boiled with ring rice cake, a wine brewed with loaves of rice cake, a wine brewed with hard boiled rice, a wine brewed with rice gruel, and a wine brewed with powdered rice gruel. 5. There were 23 kinds of utensils including measuring devices for weight and volume.

• 한국작물학회지
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• 제35권5호
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• pp.413-423
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• 1990

옥수수 양질 품종을 육성하기 위한 기초 연구로서 옥수수 유전 자원과 주요 교잡종 100여 계통에 대하여 단백질 함량과 아미노산 조성을 검토하였다. 그 결과는 다음과 같다. 1. 옥수수 유전 자원의 평균 단백질 함량은 11.5%로서 그의 문포범위는 8.0-17.3%이었다. 품종별로는 사료용 교잡종들의 단백질 함량이 9.1-11.4%이었고 찰옥수수 12.2%, 단옥수수 10.2%-13.9%이었으며 변경 opaque-2인 Qpm의 단백질 함량은 11.0%이었다. 2. 사료용 교잡종 수원 19호와 단옥수수 수원SS-2001 및 Qpm의 아미노산 조성은 대체로 glutamic acid와 leucine의 함량이 높았고 methionine은 낮았다. 품종에 따른 차이도 나타났는데 Qpm은 lysine 함량이 수원 19호나 수원 SS-2001에 비하여 1.4-1.7배 높았으며 단백가 72로서 수원 19호와 수원 SS-2001의 단백가에 비하여 높았다. 수원 SS-2001의 아미노산 조성은 수원19호와 Qpm과는 달리 threonine의 함량이 높았으며, 필수 아미노산의 총량도 많았다. 3. 분획 단백질의 양은 수원 19호와 수원 SS-2001에서는 zein이 각각 50.7%와 41.7%, glutelin이 26.8%와 30.8%이었던 반면 Qpm은 zein이 12.7%, glutelin이 55.2%, globulin 11.4%로서 zein의 함량이 낮았다. 4. 분획 단백질별 아미노산 조성에 있어서는 zein과 glutelin의 아미노산 조성은 품종간 큰 차이가 없었으나 globulin의 아미노산 조성은 Qpm과 수원 19호간 차이가 컸으며 특히 Qpm의 globulin의 lysine 함량은 10.2%로서 수원 19호에 비하여 4배 이상이었다. 5. 분획 단백질별 아미노산 조성 및 품종간 분획 단백질량을 비교하였을 때 Qpm의 opaque-2인자는 종실 단백질 중 zein함량을 억제하고 glutelin과 globulin을 증대시킴으로써 종실의 lysine함량을 증대시키는 것으로 나타났다.

• 한국작물학회지
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• 제61권4호
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• pp.277-282
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• 2016

본 연구에서는 찰옥수수 재배 시 문제가 되는 수확 후 품질 변화를 명확히 구명하고자 찰옥수수 수확시기 및 저장조건에 따른 이삭 특성의 변화를 검토하여 최적의 수확시기와 저장방법을 제시하고자 수행하였다. 1. 암이삭은 출사 후 15일에서 25일 사이에 급격히 발달하였으며 알곡 무게도 암이삭의 발달과 같은 경향이었다. 출사 후 10일에 암이삭과 알곡의 무게는 각각 78.3 g, 1.13 g이었으며, 출사 후 25일에 224.9 g과 3.61 g으로 크게 증가하였다. 반면 출사 후 30일부터 크게 줄어들어 각각 10.6%와 6.1% 감소하였다. 2. 수확시기별 전분함량은 출사 후 25일에 73%를 나타냈고, 생육초기에 비해 약 10%의 증가를 보였다. 수확시기를 결정짓는 중요한 요인 중에 경도와 당도 만을 고려하였을 경우에는 출사 후 25일이 수확적기로 판단되었다. 3. 저장기간별 알곡 경도는 수확 직후 $726g\;cm^{-2}$에서 저장 28일에 $1894g\;cm^{-2}$로 증가하였다. 총당함량은 모든 저장 온도에서 감소하였으며, 감소폭은 온도에 따라 달랐으나 $3^{\circ}C$ 및 $10^{\circ}C$보다 $0^{\circ}C$ 저장에서 작았다.