• 한국유가공학회:학술대회논문집
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• 1997.05a
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• pp.23-34
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• 1997

Calcium-stimulated ATPase ($Ca^{2+}$-ATPase) which has optimal pH value at 7.0 was found in the membrane fraction of human milk, and its enzymatic properties were studied. The purified $Ca^{2+}$-ATPase required 0.45 mM Ca ion for maximal activity. Among the nucleosides, $Ca^{2+}$-ATPase showed a higher substrate specificity to ATP and UTP than to CTP and GTP. $Ca^{2+}$-ATPase had apparent Km value of 0.065, and V max of 7.63 mol ATP hydrolyzed/mg pro-tein per min, respectively. $Ca^{2+}$-ATPase was potently inhibited by lanthanide, vanadate, and p-chloromercuribenzoate, and inactivated by EDTA, and CDTA and EGTA, but were unaffected by N-ethylmaleimide, $NaN_3$, ouabain, or oligomycin, and was completely inactivated by heating at $60^{\circ}C$ for 10 min. This enzyme activity was concentrated in the membrane fraction of the cream and skim milk membrane, but not founded in bovine milk.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.93-100
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• 2014

In general, whey obtained from various cheese batches is being reused, so as to improve the texture and to increase the yield and the nutrient value of the various final milk-based products. In fact, re-usage of whey proteins, including whey cream, is a common and routine procedure. Unfortunately, most bacteriophages can survive heat treatments such as pasteurization. Hence, there is a high risk of an increase in the bacteriophage population during the cheese-making process. Whey samples contaminated with bacteriophages can cause serious problems in the cheese industry. In particular, the process of whey separation frequently leads to aerosol-borne bacteriophages and thus to a contaminated environment in the dairy production plant. In addition, whey proteins and whey cream reused in a cheese matrix can be infected by bacteriophages with thermal resistance. Therefore, to completely abolish the various risks of fermentation failure during re-usage of whey, a whey treatment that effectively decreases the bacteriophage population is urgently needed and indispensable. Hence, the purpose of this review is to introduce various newly developed methods and state-of-the-art technologies for removing bacteriophages from contaminated whey and whey products.

• The Korean Journal of Food And Nutrition
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• v.28 no.2
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• pp.178-188
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• 2015

The purpose of this study was to investigate the association of interpersonal relationships with snack preference and the intake frequency of snacks with a primary focus on obesity index and snack preparations in upper grade (5~6th) elementary school students. A total of 719 students in Gyeongsangnam-do province were recruited and a questionnaire-based survey was conducted. Data were analyzed using the SPSS V18.0. The results were as follows : A total score of interpersonal relationships was 94.5 (full marks 125), and the scores of 7 factors consisting interpersonal relationships were over 3.50(full marks 5.00). Overweight group had the lowest score in interpersonal relationships (p<0.01) and purchase group by oneself had a low score than the other groups in snacks preparation (p<0.001). Most favorite snacks were ice cream. Additionally, the snack purchase group showed higher scores than the cook group by family in 8 types of snack and a total score of preference (p<0.05~p<0.001). Milk and dairy products had the highest score in frequency of snack intake. And purchase group by oneself or family was a higher than cook group by family (p<0.01). Interpersonal relationships showed a positive effect on preference and intake frequency of milk and dairy products but their explanation powers ($R^2$) were very low. The findings of this study provide fundamental information impact factor in snack preference and frequency of snack intake.

• Journal of Dairy Science and Biotechnology
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• v.14 no.1
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• pp.71-84
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• 1996

This study was conducted to examine the usability of sorbitol for the manufacture as low-calory ingredient and cryoprotectant against frost damage. When frozen yoghrt was made of replacing sucrose by sorbitol at yoghurt mix, the change of physicochemical and lactic acid bacteria, such as Str. thermophilus, L. bulgaricus, and mixed culture of Str. thermophilus, and L. bulgaricus(1:1), was studied during the frozen storage(-20$^{\circ}$C). During the incubation of yoghurt mix, the rapid growth of lactic acid bacteria in all sample was observed as the increase of sorbitol addition, but sample A and D were almost similar. This results suggested that sucrose could play role of effecting the growth stimulator, otherwise, sorbitol could inhibit the death of microorganism, following the genus. At the survival rate between lactic acid bacteria during freezing of -5$^{\circ}$C by ice cream freezer Str. thermophilus showed 26.19 to 34.76%, L. bulgaricus 3.97 to 5.20%, and mixed culture 17.16 to 40.87% respectively. L. bulgaricus showed the greater lethal rate than other genus. Sample C which mixed sucrose with sorbitol (1:2 ratio) was showed the lowest lethal rate. Therefore, it suggested that the use of this ration could be used for better anti-frost damage. During the storage of -20$^{\circ}$C, the number of lactic acid bacteria generally decreased in the stand point of genus and frozen storage period. The survival of lactic acid bacteria might be the addition of sorbitol which could have the effect of anti-forst damage. In all treatment, lactase activity showed the rapid decrease after freezing. During the period of frozen storage, it was shown the slow decreasing trend. In spite· of decreasing, the result during yoghurt mix incubation -5$^{\circ}$C freezing, and -20$^{\circ}$C frozen storage was different at the level. After 80 days of storage, the lactase activity was similar among all genus and sample. Despite differenting viscosity followed by genus, combination of mix, and pH, the ratio of 1 to 2(sucrose : sorbitol) showed the greatest viscosity. The water holding capacity of frozen yoghurt mix was closely related to viscosity. As increasing sorbitol amounts, hardness and cohesiveness were increased, but elastisity was decreased. The significant differences between sample was inoculated with Str. thermophilus. However, there were not significant difference from the sample inoculated with L. bulgaricus and mixed culture.

• Journal of Korean Home Economics Education Association
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• v.29 no.4
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• pp.117-131
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• 2017

This study was performed to analyze education contents related to milk in current home economics textbooks of middle school, and to investigate intake status, consumption behaviors, perception and nutritional knowledge of milk and dairy products among 364 middle school students in Gongju for improvement of milk education in home economics subjects and milk intake of adolescents. As a result, education contents of milk and dairy products in home economics textbooks currently applied in middle school were major nutrients, consumption method for balanced diet, and selection and storage of milk and dairy products, thus it tended not to match current food trend. Only 30.5% of subjects met 2 cups of milk a day, the recommended level. The main reason for drinking milk was to 'be taller' and 'to quench thirst' and there was a difference by gender(p<0.01). The rate of not participating in school milk program was 23.1% of total and its satisfaction was moderate. The most popular dairy products by subjects were ice cream, followed by yogurt and cheese, and the choice of milk was focused on 'taste' or 'expiration date'. The rate of knowing certification mark of K-MILK was low at 28.8%, and most subjects knew as 'domestic milk use'. In home economics class, experience-based learning such as cow ranch experience was the most preferred instruction method for milk followed by laboratory practice and lecture, and there was a difference by gender(p<0.001). Perception degree of milk and dairy products was moderate and male subjects were more positively perceived than female subjects(p<0.01). Nutritional knowledge level of milk and dairy products was moderate and female subjects were higher than male subjects(p<0.01). Therefore, education contents of milk and dairy products of home economics textbooks of middle school should be centered on real life in accordance with food trend, and applied student participation-based instruction methods such as experience-based learning. In addition, it is necessary to enhance taste and merchandise of milk and to provide them with preferred milk and dairy products in school milk program for improvement of milk intake of adolescents.

• Korean Journal of Human Ecology
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• v.7 no.4
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• pp.5-23
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• 2004

This study was done to provide basic information for nutrition education and meal planning preference, Children's preference according to cooking method is high in fruit. drink, fried foods, dish food, but low in Sangchae, Sukchae, and Jangachies. The preference of staple food was that the most preferred foods were plain rice in rice, chicken gruel in gruels, rolled rice in one dish foods. and Jajangmyeon in noodles. The preference of side dishes was that the most preferred foods were seaweed in soups, Kimchi in Chigaes, beef and pork rib in steamed foods, beef in braised foods, Bulgogi in grilled foods, egg-fry in pan fried foods, Ddukbokki in stir-fried foods, pork cutlet in fried foods, Dotorimuk in Sangchaes, fruit in salads, bean sprouts in Sukchaes, Baechu Kimchi in Kimchies and Danmuji in Jangachies. The preference of snack was that the most preferred foods were citrus in fruits, Kkuldduk in rice cakes, hotdog in bread, ice cream in milk and dairy products and fruits juice in drink.

• Korean Journal of Community Nutrition
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• v.19 no.2
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• pp.122-132
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• 2014

Objectives: This study was conducted to investigate the vitamin D status and to determine the association between serum 25-hydroxyvitamin D [25(OH)D] concentrations and consumption frequencies of vitamin D rich foods in Korean adults and older adults. Methods: Subjects were 10,374 adults and 2,792 older adults participating in the 2008-2009 Korea National Health and Nutrition Examination Survey (KNHANES). Consumption frequencies of vitamin D rich foods were estimated by using a qualitative food frequency questionnaire (FFQ). Eleven food items such as beef, egg, mackerel, tuna, yellow corvina, pollack, anchovy, mushroom, milk, yogurt, and ice cream were selected as vitamin D rich foods based on previous research. Results: The proportions of deficiency (< 12 ng/mL), inadequacy (12-20 ng/mL) and sufficiency (${\geq}20ng/mL$) of serum 25(OH)D concentrations from June to November and December to May in adults were 8.8%, 42.3%, 48.8%, and 28.2%, 52.8%, 19.1%, respectively. The proportions of deficiency, inadequacy and sufficiency of serum 25(OH)D concentrations from June to November and December to May in older adults were 10.1%, 32.4%, 57.5%, and 24.1%, 45.4%, 30.5%, respectively. The mean serum 25(OH)D concentrations in adults were positively related to the consumption frequencies of mackerel, anchovy, all fish, milk and milk dairy products. The mean serum 25(OH)D concentrations in older adults were positively related to the consumption frequencies of yellow corvina and negatively related to the consumption frequencies of ice cream. Conclusions: Our results suggest that Korean adults were more deficient in serum 25(OH)D concentrations than older adults. The consumption of vitamin D rich foods may affect vitamin D status in Korean adults. Further studies are required to confirm these findings.

• The Korean Journal of Community Living Science
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• v.19 no.3
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• pp.335-351
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• 2008

Adequate nutrients intake and regular eating habit are so important for the students to develop physical and mental health, and they contribute significantly for the development of intellectual capacity. The intake of simple sugar contained in the processed foods is known to have been related not only with such physical problems as obesity and diabetes but also with hyperactivity during growing period. This study analysed the effects of carbohydrate processed snacks on the middle school students' emotional intelligence and intended to demonstrate the correlation and the influence of the foods. The subjects of this study were 476 the 1st grade middle school students sampled from two public middle schools of Gyeonggi Province, Korea. Questionnaire contained 47 questions including the kinds of sugar containing processed foods, the frequency of intake, the frequency of normal diet, and the emotional test. All data obtained in this study were processed by SAS 8.2 program. 77.9% of the students had snacks more than once a day and the favored foods were in the order of bread, cookies, fruit, milk and dairy products, flour foods, ramen and ice cream. Less of the sugar contained processed snacks consumed high emotional intelligence showed(p<0.001). And low intake of carbohydrate processed snacks linked with having more regular meals and the higher levels of emotional intelligence. There was no gender difference in consuming simple sugar containing processed foods, however, out of these foods, carbonated drinks, ramen and pizza affected significantly the emotional intelligence of the male students. It was found that sugar contained processed snacks affect the eating habits like meal skipping and the emotional intelligence. It is determined that the effects of carbohydrate processed snacks on emotional intelligence can not be denied.

• Korean Journal of Community Nutrition
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• v.17 no.3
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• pp.302-311
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• 2012

The purpose of this study was to provide preliminary data for better safety control over children's preference foods sold in school stores. The survey was conducted from June to July 2009, to collect 749 types of children's preference foods sold in 150 middle and high school stores nation-wide excluding Jeju Island and general and nutrition information were analyzed. Out of 749 types of snack food items, 689 and 602 snacks were sold at high school and middle school stores respectively. Among children's preference foods, cookies, bread, and ice-cream were the main items. Among them, 98% of snacks were domestic products and the price range of each individual snacks were mostly between 600 and 900 won. 27.8% of children's preference foods sold were found to be in the high calorie/low nutrition food group. Even though the proportion of candy and fruit/vegetable beverages sold were not high, their proportion in high calorie/low nutrition snack group were higher than 68.1%. Among the children's preference foods sold in middle and high school stores, carbonated drinks and ramen were continuously sold in certain middle and high schools, even though sales were prohibited. This study concludes that government, corporations and retailers should work together in developing healthier children's snack distribution environment. In addition, dairy products, which take up 15% of children's preference food, should be diversified to meet their nutrient requirements.

• Nutrition Research and Practice
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• v.5 no.2
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• pp.140-149
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• 2011

This study was conducted to evaluate the rate of obesity of 212 women (age 45-60 years) in Seoul and the Kyunggi area through analysis of BMI and the dietary life factors related to obesity using a survey on dietary habits, dietary assessment, and nutrient intake. The height of the underweight group was taller than normal. The height of the obese group was equal to that of the normal group, but the weight was 8.5 kg greater than the normal group. Women in the underweight group consumed meals irregularly, and only 33.4% ate breakfast. Additionally, the rate of overeating was low in the underweight group, and milk, dairy products (yogurt, etc.), fruit, and fruit juice were consumed more than once a day. It was found that 62.1% of the women in the obese group never ate out, and the rate of eating one serving of fruit, drinking one cup of fruit juice, and eating various kinds of foods was high. The average point of women's dietary life was $21.9{\pm}2.9$, and 12.7% of all women responded that their dietary life was good. However, in the obese group, only 6.9% of the women reported that their dietary life was good. Evaluation of snacking habits revealed that the underweight group consumed a high level of carbonated drinks and ice cream, whereas for in the obese group, 24.1% of the women consumed milk and its products and 5.6% regularly consumed fast and fried foods. Evaluation of nutrient intake revealed that the consumption of energy, protein, vitamin A, vitamin $B_1$, $B_2$, $B_6$, niacin, vitamin C, and vitamin E was high in all of the groups, but the intake of folic acid in the underweight group was lower than the required level. Overall, 24.1% of the women in the obese group were found to have metabolic diseases, mostly hypertension (43%). In conclusion, a balanced diet to avoid excessive nutrient intake is needed to prevent obesity.