조리 및 저장에 따른 시금치 엽산 함량의 변화 - 조리시간에 따른 엽산의 열파괴 손실과 조리수를 통한 손실의 비교 -

민혜선(Hye-Sun Min) 한국식품영양과학회 1998 한국식품영양과학회지 Vol.27 No.2

가열조리가 시금치의 엽산 함량에 미치는 영향을 조사하기 위하여, 증류수에 시금치를 넣고 1, 2, 3, 4, 5, 10, 20분간 가열 조리하였다. 조리된 시금치의 엽산 함량은 1분 후 80.7%, 2분 후 33.4%, 3분 후 12.6%로 급격하게 감소되었고, 20분 후 5.5%로 감소되었다. 그러나, 시금치와 조리수의 엽산 함량을 합하면 가열조리 1분 후 101.1%, 2분 후 68%, 3분 후 51.3%, 20분 후 52.0%를 나타내어 4분 이상의 가열조건에서는 총 엽산 함량이 크게 변하지 않았으나 대부분의 엽산이 조리액으로 유출되었다. 가열조리에 의한 시금치내 엽산 함량의 저하현상은 2분과 3분 사이에 급속히 진행되었으며, 조리수를 통한 유출에 의한 엽산의 상대적 손실율은 가열조리 시간이 1분일 때 20.2%, 20분일 때 88.8%로 조리시간이 길어짐에 따라 크게 증가하였다. 시금치를 전자레인지로 가열 조리했을 때 보유된 총 엽산 함량은 물로 끓여서 조리한 경우와 유사하였으나, 전자레인지를 이용한 조리에서는 소량의 조리수를 사용하므로 조리수를 통한 엽산의 손실이 낮아서 시금치 조직에 보유되는 엽산량은 더 높았다. 시금치를 냉장보관하였을 때 1~2주 후의 엽산 보유량이 90% 이상으로서 시금치의 엽산이 냉장저장 조건에서는 비교적 잘 보유되는 것으로 조사되었다. The effects of cooking methods and storage time on folate content in spinach were determined by boiling for 1, 2, 3, 4, 5, 10, and 20min in distilled water or by microwave blanching for 20, 40, 60, 80, 100 sec. The folate content of cooked spinach was decreased to 80.7% after 1min boiling, and to 5.5% after 20min boiling. The folate recovered from the cooked spinach and cooking water was 101.1% after 1min, 68.0% after 2min and 51.3% after 3min. The relative folate content leached out of the cooked spinach into the cooking water varied from 20.2% after 1min boiling to 88.8% after 20min boiling. Total folate content of spinach was decreased to 45% by microwave heating for 40sec. However, the spinach cooked by microwave heating retained more folate due to the minimal loss of folate into cooking water. More than 90% of folate content of spinach was retained during 1 to 2 weeks of storage at 4℃.

일부 중학생의 체중에 따른 체중인식, 체중조절 및 식행동에 관한 연구

김지은(Ji Eun Kim),민혜선(Hye Sun Min) 대한지역사회영양학회 2008 대한지역사회영양학회지 Vol.13 No.1

This study investigated the association between the weight status of middle school students and the various weightrelated characteristics including desired weight, weight perception, weight-related practice, physical activity, and overeating behavior. Questionnaires were administered to 473 middle school students (178 boys and 295 girls) in Daejeon. Boys and girls were divided into three groups respectively; (1) underweight (BMI < 5th percentile) (2) normal weight (5th percentile≤ BMI < 85th percentile) (3) overweight (BMI≥85th percentile). Using BMI calculated from measured height and weight, 14.0% of boys and 6.8% of girls were underweight, and 16.3% of boys and 14.2% of girls were overweight. However, among this sample of students, 38.4% of boys and 13.6% of girls perceived themselves as underweight and 29.4% of boys and 44.9% of girls perceived themselves as overweight. We found that overweight students reported their body weights lower and their heights higher compared to nonoverweight students, resulting in an underestimation of BMI. Based on desired BMI, 79.9% of the girls desired to be underweight and 73.0% of the boys desired to be normal weight. Overweight or normal weight students were less satisfied with their body weights than underweight students. Girls had more weight control experience and concern compared to boys. Overweight girls spent longer times in watching TV compared to non-overweight girls (p < 0.001) and had more overeating behaviors (p < 0.05). Overweight students reported that they ate snacks less frequently than non-overweight students, which may be due to their tendency to report less eating. In conclusion, significant gender differences and weight status differences existed in weight perception, weight satisfaction, and weight control experience and concern. Because perception of overweight is likely to lead to unhealthy eating behaviors and weight control, efforts for adolescents to improve accuracy of weight perceptions and to understand the benefits of being healthier are needed. (Korean J Community Nutrition 13(1) : 13~23, 2008)

학령기 아동이 지각하는 어머니의 양육태도별 아동의 체중 및 식습관 비교

최윤정(Yun Jung Choe),민혜선(Hye Sun Min) 대한지역사회영양학회 2009 대한지역사회영양학회지 Vol.14 No.1

Effective parenting attitudes have been known to be associated with children`s health practices including dietary intake and physical activity. The objective of this study is to compare children`s body weights and eating habits by maternal parenting attitudes. Data were collected at school (N=396; 4th and 5th grade students) using self-administered questionnaires on maternal parenting attitudes, eating habits and physical activity. Parenting attitudes were categorized as 1 of 4 parenting attitudes (overprotective, authoritarian, democratic, and neglectful) using affection and control median cut points. Children`s body weights, frequency of breakfast, eating out and fastfood, and physical activity were compared by maternal parenting attitudes. Children`s body weights were related with mother`s employment status (p<0.05) and parenting attitudes (p<0.01). Children of unemployed mothers were more likely to be overweight. Children of neglectful mothers (p<0.01) were more likely to be underweight, compared with children of mothers with other parenting attitudes. Since, unfortunately, the number of children of neglectful mothers was very limited in this study, we could hardly assess eating habits of children of neglectful mothers. Children of authoritarian mothers ate breakfast more regularly (p<0.05), but ate snacks less regularly (p<0.01). Children of democratic mothers ate fastfood less frequently (p<0.01) and ate snacks more regularly (p<0.01). Meanwhile, children of overprotective mothers ate breakfast less regularly (p<0.05) and ate out less frequently (p<0.01). However, maternal parenting attitudes were not related to children`s physical activities. In conclusion, the maternal democratic parenting attitude was associated with healthy eating habits including regular snack time and less fastfood. On the other hand, the maternal neglectful parenting attitude was associated with high risk of children`s underweight. Understanding the mechanism through which parenting attitude is related with underweight risk and healthy eating habits may lead to the development of better interventions. (Korean J Community Nutrition 14(1):77~86, 2009)

에너지 파일의 열적거동 인자분석

정상섬(Jeong Sang-Seom),송진영(Song Jin-Young),민혜선(Min Hye-Sun),이성준(Lee Sung-June) 대한토목학회 2010 대한토목학회논문집 C Vol.30 No.6

본 논문에서는 지열을 이용한 PHC, 강관, 동관말뚝 형태인 에너지 파일의 지반 조건별 내부 충진재 열전도도 효율과 겨울철 열교환기 내부 순환수의 유속별(0.3㎧, 0.6㎧, 0.9㎧) 24시간 운용(8시간 운용, 16시간 대기)시 에너지 파일의 열전달 거동을 ABAQUS(ver 6.10)와 FLUENT(ver 6.3.26)를 사용하여 분석하였다. 분석결과 말뚝 재료와 지반조건별 열전달 효율은 동관, 강관, PHC 말뚝순으로 열전달 효율이 좋은 것으로 나타났으며, 말뚝 중 PHC 말뚝 형태의 에너지 파일을 유속별 8시간 운용에 따른 분석결과 경계조건이 일정할 때 유속 조건 중 유입속도 0.6㎧ 일 때 평균 유출온도(275.4K) 및 열교환율(103.1 W/m)로 경제적인 유속으로 판단되었으며, 8시간 운용 후 초기조건과 동일하게 16시간동안 지열이 에너지파일에 공급 시 정상상태와의 온도차는 0.1K로 열량이 충분히 충전되어 에너지 파일의 겨울철 8시간운용 - 16시간대기는 운용상 적절한 것으로 판단된다. This paper presents the thermal conduction analysis (using ABAQUS ver 6.10 and FLUENT ver 6.3.26) of geothermal energy for PHC, steel and copper energy piles by considering subsurface environment, thermal efficiency of grouting materials, and fluid velocity of circulating fluid. Results show that higher thermal efficiency for copper pile is observed followed by steel and PHC piles depending on the grouting materials and subsurface condition. The fluid velocity of 0.6㎧ presents most efficient outflow temperature (275.4K) and heat exchange rate (103.1 W/m) for the case of PHC pile during 8 hours operation. Analysis of operation schedule concludes that 16 hours of stand-by allows charging geothermal energy following 8 hours operation in winter season is most appropriate with 0.1 K of temperature difference from the steady-state condition.

단체급식소에서의 환경운동이 환경문제 인식도와 환경보호 실천도에 미치는 영향

전무영,민혜선 대한영양사협회 2000 대한영양사협회 학술지 Vol.6 No.2

Environmental pollution induced by food wastes is considered as one of very serious problems in the world, and it is the most important to reduce the production of food wastes. In this study, environmental campaign for reducing food wastes was conducted by applying various campaign methods using such as a bulletin board, intra-network, slogans & posters and news letters, as well as some systems such as penalty and prize in a business & industry foodservice. We investigated customers' recognition and execution degree before and after environmental campaign for the purpose of analyzing the changes of customers' attitude by the campaign. The subjects of this study had generally high level of recognition of environmental problem(3.09 point) compared to the execution degree(1.88 point) (Max. 5 points), implying necessity for the induction of actual execution of food wastes reduction by continuous environmental campaign. After environmental campaign, the recognition of environmental problem related to food wastes was significantly increased from 3.09 point to 3.29 point (p<0.001), and the execution degree for food wastes reduction was also greatly increased from 1.88 to 2.70 point (p<0.001). These changes indicated that campaign for food wastes reduction has raised customers' recognition and execution for environmental protection.