본 연구는 어린이 기호식품에 대한 초등학생들의 인식과 섭취 실태/행동을 알아보고, 또 성별 및 학년과의 연관성을 알아보고자 수행되었다. 일개 도시의 13개 초등학교 주변에서 무작위 추출된 초등학생 306명(남 188명, 여 118명)에 대하여 직접면담법에 의한 설문조사를 수행하였다. 전체적으로 20% 이상의 학생이 어린이 기호식품에 대한 지식이 없었으며 또 어린이 기호식품에 대한 정보원이 없었다. 또한 60% 이상의 학생이 1주일에 1~2회 이상 학교주변 어린이 기호식품 판매업소를 이용하는 것으로 나타났다. 어린이 기호식품에 대한 정보 습득 경로로는 학교가 37%로 가장 많고, 다음으로 가정 16%이었다. 어린이 기호식품에 대한 의식 및 행동을 나타내는 요인들 중에서 지식과 정보 습득 경로는 성별과 유의한 연관성이 있었다(p < 0.05). 또 지식, 정보 습득 경로, 태도, 섭취 이유에 있어 학년과 유의한 연관성이 있었다(p < 0.05). 남자 어린이가 여자 어린이보다 지식 수준은 높았으나(p < 0.05), 태도는 낮고 또 섭취 빈도가 높았다. 학년이 높을수록 어린이 기호식품에 대한 지식과 태도 수준이 높아지고 다양한 정보 습득 경로를 가졌으나(p < 0.05), 또한 섭취 빈도가 높았다. 이러한 결과는 조사대상자의 지식과 태도/행동의 불일치를 나타낸다. 그러므로 학생들의 주요 정보 습득 경로인 학교급식 프로그램과 학교 및 가정에서의 식품위생/안전교육이 더욱 향상되어야 함을 나타낸다. 더불어 학교주변에서 불량식품에 대한 규제도 강화되어야 할 것이다.

This study was performed to investigate hygienic behavior of food workers on the awareness of hand-washing, and the microbial load of their hands. This study focused on the comparison of fast food restaurant workers and full-service restaurant workers. A questionnaire survey and microbiological analysis were carried out for thirty fast food restaurant workers and forty full-service restaurant workers. Samples for microbiological analysis were collected through the glove-juice method from the hands of the food workers, and were analyzed for the presence of aerobic plate counts, total coliforms, fecal coliforms, Escherichia coli, Staphylococcus aureus, and Salmonella spp. Microbiological analysis was done according to the Food Code of Korea. In the survey, significant differences (p < 0.05) were found between the fast food restaurant workers and full-service restaurant workers in the use of hand washing tools and method of turning off water. More full-service restaurant workers responded to wash their hands after touching face, hair, or clothes; after handling raw food materials, and more fast food restaurant workers periodically (p < 0.05). Aerobic plate counts were higher in fast food restaurant workers while total coliforms were higher in fullservice restaurant workers (p < 0.05). No remarkable difference was found between the two groups in the load of fecal coliforms, E. coli, S. aureus, and Salmonella spp. Poor hand hygiene practices were indicated by the positive results for E. coli, S. aureus, and Salmonella spp. on the hands of some food workers in both groups. The findings of this study emphasize the need for strict adherence to hand hygiene compliance among the food workers.

Multi-elements doped TiO2 was prepared as a new photocatalyst in order to decrease the band gap of TiO2 by sol-gel process which can provide the large active sites of TiO2. Multi-elements were doped by using a single precursor, tetraethylammonium tetrafluoroborate (TEATFB). By the benefit of large specific surface area of TiO2 prepared by sol-gel process, catalysts showed initial fast removal of dye. The photoactivity showed that the doped catalysts significantly promote the light reactivity than undoped TiO2. The commendable photoactivity of prepared catalysts is predominantly attributable to the doping of anions which may reduce the band gap.

A nanocomposite consisting of Fe3O4 and MWCNT was produced via sol-gel technique using FeCl3 along with MWCNT by calcination at 300℃. The degradation effect of rhodamine B dye has been investigated under UV illumination in a darkroom. The degradation reaction was studied by monitoring the discoloration of dye as a function of irradiation time using UV-visible spectrophotometeric technique. The Fe3O4-MWCNT samples have continuous degradation ability under the UV illumination with the first order kinetics and the dye removal was better than in the pristine Fe3O4. The resultant composite catalyst was found to be efficient for the photo-Fenton reaction of the dye.

In order to investigate the effect of doping C, N, B and F elements on TiO2 for reducing the band gap, the heat treatment of TiO2 was carried out with tetraethylammonium tetrafluoroborate. Through XRD and XPS analysis, the C, N, B and F doped anatase TiO2 was confirmed. According to the increase of temperature during treatment, the particle size was increased due to aggregation of TiO2 with elements (B, C, N and F). To investigate the capacity of photocatalyst for degradation of dye under solar light, the degradation of acridine orange and methylene blue was conducted. The degradation of dyes was carried out successfully under solar light indicating the effect of doping elements (B, C, N and F) on TiO2 for reducing the band gap effectively.

This study was performed to investigate the changes of amount of S. typhimurium during cooking processes using pork and japchae (a Korean food which is made from meat, vegetables and noodles), and to support a practical application to develop a hazard analysis critical control point (HACCP) model. The pork was purchased in a retail shop, cut (0.5 cm × 10 cm × 10 cm, 25 g), tested for Salmonella contamination (results : negative), inoculated with S. typhimurium (10^7 CFU/g), then treated in various conditions related to cooking. After thawing for 24 hours in various conditions, the number of S. typhimurium was increased to 10^(10) CFU/g at a refrigerated temperature (4-10℃), and to 10^(21) CFU/g at room temperature (22-29℃). After thawing in a microwave oven for 40 seconds, the number of S. typhimurium increased to l0^8 CFU/g. During the thawing period, the number of S. typhimurium increased over time. At the refrigerated temperature, the number of the bacteria was 10^(10) CFU/g after 24 hours, 10^(13) CFU/g after 48 hours, and 10^(20) CFU/g after 72 hours. At room temperature the number of bacteria reached 10^(11) CFU/g in 2 hours, 10^(15) CFU/g in 4 hours, 10^(16) CFU/g in 8 hours, 10^(18) CFU/ g in 12 hours, and 10^(21) CFU/g in 24 hours. After cooking in a frying pan (150±7℃) for 3 minutes, the bacterial count was 10^6 CFU/g. After cooking in hot water for 20 minutes, the bacterial count was 10^7 CFU/g at 60℃, 10^6 CFU/g at 63℃, and 10⁴ CFU/g at 65℃. The fried pork was mi×ed with cooked vegetables, noodles, sesame oil, sesame seeds, and seasonings to make Korean japchae. This process took 10±2 minutes. The bacterial count in the japchae increased to 10^7 CFU/g from the count of 10^6 CFU/g of the fried pork before it was mixed with the other ingredients. These results indicate that the amount of S. typhimurium is effected by various different cooking processes. This study can suggest that pork should be cooked in water at over 65℃ for 20 minutes in order to prevent food poisoning, if the pork is contaminated with S. typhimurium. The presence of S. typhimurium in the raw pork is identified in an HA for japchae, and the primary CCP for japchae is inadequate cooking (cooking method and time/temperature). We need to standardize time-temperature-size and amount of pork in cooking japchae, because pork is usually cooked in ordinary frying pans when we make this food.

This study was performed to investigate the possible effect of Bacillus subtilis which is the predominant species of bacteria in Korean soy sauce, soy paste, and Meju (soybean cake) on the growth and aflatoxin production of Aspergillus parasiticus ATCC 15517. The microorganisms were grown in a modified APT broth and incubated at 30℃ for 12 days. Aflatoxins were determined using high performance liquid chromatography (HPLC). A remarkable inhibition of the growth of Aspergillus parasiticus was observed during the incubation period when in the presence of B. subtilis (mixed culture). Dry mycelial weight in the mixed culture was significantly reduced by 85.3% in comparison to the control at the end of the incubation period (p$lt;0.01). Lower levels of aflatoxins were found in the mixed culture than in the monoculture. At the end of the incubation period aflatoxin production was significantly inhibited by more than 50% (p$lt;0.05). These results indicate that B. subtilis mainly inhibites the growth and aflatoxin production of toxigenic Aspergillus in Meju, soy sauce and soy paste. Although its effect on aflatoxin production was less pronounced, we . could expect more inhibition by another bacteria related with fermentation in Meju.

발효식품이 유해곰팡이에 의한 발암물질(aflatoxin)생성에 미치는 억제효과에 관한 연구의 일환으로 유산균 및 유산균 발효유가 Aspergillus parasiticus ATCC 15517의 성장과 aflatoxin 생성에 미치는 영향을 실험하였다. 발효유를 일정 농도별로 첨가한 YES 배지에서 Asperigillus parasiticus를 배양하여 그 성장과 배양물의 변화를 관찰하고 HPLC에 의하여 aflatoxin을 분석하였다. 그 결과 배양말기에 대조군에 비하여 건조 균체량, 배양물의 PH, 그리고 aflatoxin 생성량 등이 낮게 나타났다(p<0.05). Aflatoxin B₁은 48.6~58.1%가 감소되었으며 G₁은 29.8~34.2%가 감소되었다. 이 발효유의 발효에 사용된 유산간균(Lactobacillus casei)과 A. parositicus를 변형 APT 배지에서 혼합배양한 결과 A. parasitious 단독배양의 경우에 비하여 균체량이 배양 5일째까지는 현저하게 억제되었으나 배양 말기에는 유의한 차이를 보이지 않았다. 또한 배양 말기에 단독배양의 경우보다 pH가 훨씬 감소되고(p<0.05) aflatoxin의 생성량도 감소되었다. 이로부터 발효유는 유해곰팡이인 A. parasiticus의 성장과 aflatoxin 생성을 억제시키는 효과를 가짐을 알 수 있으며, 이는 발효에 관여한 미생물의 경쟁뿐만 아니라 유산균의 대사산물에 의한 영향으로 보여진다.

쌀에 대하여 aflatoxin 생성을 위한 기질로서의 능력을 알아보기 위하여 현미(청청벼) 시료에 Aspergillus parasiticus를 접종하고 조건을 달리하여 저장하면서 aflatoxin B₁의 생성을 관찰하였다. 시료중의 aflatoxin B₁의 분석은 ELISA를 이용하여 수행하였다. 현미 시료에서 aflatoxin B_1 생성에 가장 좋은 온도는 28℃였으며, 시료의 수분함량을 15.8%로 증가시킨 경우 aflatoxin B₁의 생성이 유의하게 증가하였고 (p<0.05), 고압증기멸균시킨 시료는 aflatoxin B_a 생성에 보다 효과적인 기질이 되었다. 실온에서 3개월 동안 저장한 현미에서는 15일 동안 저장한 경우에 비하여 aflatoxin B₁ 생성이 유의한 증가를 보였다(p<0.05). 따라서 저장온도 및 수분함량이 쌀에서도 aflatoxin B₁ 생성에 영향을 미치는 바를 나타내었으며, 또 시료의 상태 및 저장기간도 쌀에서 aflatoxin 생성 위험요인으로 작용할 수 있음이 제시되었다. 이러한 결과로부터 쌀이 aflatoxin 생성에 좋은 기질이 될 수 있는 것으로 평가된다.

HPLC에 의한 주요 aflatoxins(afatoxin B₁, B₂, G₁ 및 G₂)의 동시 분석에서 postcolumn 유도체화법을 시도하였다. Electrochemical cell(Kobra-cell)을 사용한 postcolumn 유도체화법은 기존의 precolumn 유도체화법보다 분석시간을 단축하였으며(약 1/2 단축), 더 안전하고, 향상된 분석능을 보였다. Aflatoxin B₁과 G₁의 경우 10~100 ppb에서, 그리고 B₂와 G₂의 경우 3~30 ppb에서 직선성을 나타내었다. Aflatoxin B₁과 G₁은 각각 88.9% 및 100.5%로 양호환 회수육을 보였다. Aflatoxin B₂와 G₂의 경우 분리도는 우수하였으나 회수율에 있어서 변이가 크게 나타났다.

The main problems contributing to food poisoning outbreaks in institutional settings and a home were reviewed and analyzed through the epidemiological investigations of food poisoning. The major documented factors included improper holding temperatures, inadequate cooking, poor personal hygiene, cross-contamination and contaminated equipment, food from unsafe sources, failure to follow food hygiene policies, and lack of education, training, monitoring and supervision. Usually more than one factor contributed to the development of an outbreak. (1) Use of improper holding temperatures was the single most important factor contributing to food poisoning. They included improper cooling, allowing a laps of time (12 hours or more) between preparing food and eating it, improper hot holding, and inadequate or improper thawing. Food thermometers were not used in most of the instances. (2) In inadequate cooking, the core temperature of food during and after cooking had not been measured, and routine monitoring was limited to recording the temperature of plated meals. Compared with conventional methods of cooking, microwave ovens did not protect against food poisoning as effectively. Centralized food preparation potentially increased the risk of food poisoning outbreaks. (3) Poor personal hygiene both at the individual level (improper handwashing and lack of proper hygienic practices) and at the institutional level (poor general sanitization) increased the risk of transmission. Person to person transmission of enteric pathogens through direct contact and via fomites has been noted in several instances. (4) Obtaining food from unsafe sources was a risk factor in outbreaks of food poisoning. Food risks were high when food was grown or harvested from contaminated areas. Possibilities included contamination in the field, in transport, at the retail site, or at the time it was prepared for serving. (5) Cross-contamination and inadequate cleaning/handling of equipment became potential vehicles of food poisoning. Failure to separate cooked food from raw food was also a risk factor. (6) Failure to follow food hygiene policies also provided opportunities for outbreaks of food poisoning. It included improper hygienic practices during food preparation, neglect of personnel policies (involvement of symptomatic workers in food preparation), poor results on routine inspections, and disregarding the results and recommendations of an inspection. (7) Lack of formal and in-service education, training, monitoring, and supervision of food handlers or supervisors were critical and perhaps neglected elements in occurrences of food poisoning.

The quality changes of hams and sausages in refrigerated storage were investigated. Seven types of hams and six types of sausages produced in Korea were collected from markets and stored at 10℃ according to the Food Code of Korea, and then chemical, microbiological, textural and sensory characteristics were evaluated at 30, 40 and 50 days. The proximal analysis showed considerable variation in fat with less variation in moisture and protein. The pH values of hams and sausages slightly changed with no consistent difference. Water activity values of all samples except one type of sausage were consistent over time in refrigerated storage. No purge losses of hams were observed except two types of samples in the intial stage. Several types of sausages showed purge losses with no consistency and one type of sausage showed consistent purge losses (0.44-11.29%) during the storage. The volatile basic nitrogen (VBN) content of hams and sausages was still within 20 mg% (Standard and Specification of Korea) on the 50th day, although the VBN of all samples significantly increased over time (p$lt;0.05). The thiobarbituric acid (TBA) values of hams and sausages were well below 1.0 during the storage, although the TBA values of all samples significantly increased (p$lt;0.05). However it was noticed that one type of ham and two types of sausages showed TBA values of 0.945, 0.928 and 0.978, respectively. All the standard plate counts (SPCs) of hams during the storage period showed a level below 30 CFU/g except one type of sample with 10³ CFU/g at 50 days. All the SPCs of sausages showed a level below 50 CFU/g except one type of sample with 10² CFU/g and two types of samples with 10⁴ CFU/g on the 50th day. Coliform groups were not counted in all samples during the storage. Instrumental texture analysis showed that springiness, cohesiveness, chewiness, gumminess and adhesiveness slightly changed with no consistent difference. The hardness of the hams showed a decreasing tendency, and the hardness of the sausages an increasing tendency with no significant difference. Sensory evaluation for color, flavor, taste, texture and overall acceptability showed decreasing tendencies over time (p$lt;0.05). The scores of the five sensory characteristics maintained the medium level of quality at the termination of the experiment. Although the results indicated that the ham and sausage samples were acceptable after the 50 days' storage at 10℃, the shelf-life of the samples should be determined considering the rapid growth of bacteria and the high TBA values at 50 days.

This study was performed to investigate the induction of experimental atherosclerosis in rats and inhibitory effects of aloe vera on progression of atherosclerosis in rats. A dose range finding study of cholesterol and vitamin D₂ for the induction of atherosclerosis and studies on the subchronic effect of aloe vera and on the chronic effect of aloe vera were carried out. A total of 3-week old 125 male rats of Sprague-Dawley were divided into 25 groups and fed with the diet containing cholesterol (0.1, 0.2, 0.3, 0.5, 1.0 and 2.0%) and vitamin D₂ (500, 5000, 50000 and 500,000 IU/100 g) for 4 weeks. 35 male rats were divided into 7 groups and fed with the diet containing aloe vera with 1.0% of cholesterol and 50,000 IU/100 g of vitamin D₂ for 4 weeks. 200 male rata were divided into 5 groups and fed with cholesterol and vitamin D₂ for 6 and 12 months. Growth, clinical and pathological changes of rats in the three experiments were observed. The results were as follows: 1. In the dose-range finding study, feed intake, feed efficiency ratio and weight gain were significantly decreased and relative liver, heart, kidney and stomach weight to body weight were increased in all of the feed groups containing 500,000 IU/100 g of vitamin D₂. Serum biochemical values of total cholesterol, high-density lipiprotein cholesterol (HDL-cholesterol), triglyceride, calcium, inorganic phosphorous and chloride of male rats in treated groups. The aorta and coronary artery of rats in all of the diet group containing 500,000 IU/100 g of vitamin D₂ showed typical atheroaclerotic lesions. 2. Male rats fed with the diet containing aloe vera with 1.0% cholesterol and 50,000 IU/100 g of vitamin D₂ for 6 and 12 months did not show significant difference of diet intake and weight gain, and relative organ weight. The level of serum HDL-cholesterol and triglyceride recovered to the normal range by the aloe vera ingestation. 3. The aorta showed irregular appearence in the tunics intima with swelling, necrosis and calcification. The aorta of rat fed aloe vera diet showed no pathological lesions such as atherosclerosis of aorta. Aloe vera could have a helpful effect of vitamin D₂ and cholesterol induced atherosclerosis in rats. Long-term supplementation of aloe vera may slow down the process of experimental atherosclerosis in rats have effects on the development of atherosclerosis.