Sulfur and nitrogen co-doped carbon dots (NSCDs) were quickly synthesized by the microwave-assisted method from triammonium citrate and thiourea. NSCDs showed a quantum yield of 11.5% with excitation and emission bands at 355 and 432 nm, respectively. Also, a fluorescence quenching was observed in the presence of Pb(II) ions, and the as-synthesized CDs were used as a sensitive probe for detecting Pb(II) in water and food samples. The results showed the optimal conditions for Pb(II) determination were CDs concentration of 0.02 mg mL− 1 at pH 6.0–7.0 and an incubation time of 20 min. The relative fluorescence intensity of NSCDs was proportional to Pb(II) concentrations in the range of 0.029–2.40 and 2.40–14.4 μmol L− 1 with a correlation coefficient (R2) of 0.998 and 0.955, respectively, and a detection limit of 9.2 × 10– 3 μmol L− 1. Responses were highly repeatable, with a standard deviation below 3.5%. The suggested method demonstrates the potential of a green, fast, and low-cost approach for Pb(II) determination in water, tea, and rice samples with satisfying results.

본 연구는 감마선 및 전자선 조사에 의한 닭고기 원료 사료 내에 존재하는 주요 위해 미생물을 비열처리 살균 효과를 검증하기 위하여 진행되었다. 일반세균, E. coli 및 Salmonella의 위해 미생물을 분쇄 닭고기 원료사료에 접종 후 3, 5, 7, 10 kGy의 전자선과 감마선으로 조사하였다. 전자선과 감마선 모두 3 kGy의 조사 시 시험된 미생물을 검출 한계 이하로 사멸시켜 분쇄 육류 원료 사료의 경우 3 kGy의 흡수선량이 충분한 비열 살균 조건임을 보여주었다. 방사선 조사에 의한 원료 사료의 품질 지표 변화를 알아보기 위하여 분쇄 닭고기의 조사 처리 후 pH 변화, 색도 측정, 전자코 이취 분석을 수행하였다. pH와 색도의 경우 감마선 및 전자선 조사에 의해 유의미하게 변화하지 않는 것으로 나타났다. 전자코 이취 시험의 경우 감마선 조사의 경우 3 kGy의 저선량 조사부터 이취가 발생되기 시작하였으며 10 kGy 조사 시 급격하게 이취의 정도가 증가하는 것으로 나타났다. 전자선 조사 역시 3 kGy의 조사부터 이취가 발생하였으며 5 kGy의 선량 이후 흡수선량이 증가함에 따라 이취가 점진적으로 증가하였다. 본 연구 결과 3 kGy의 저선량에서도 닭고기를 원료로한 펫푸드의 비열 살균 효과를 충분하게 이루어짐을 확인하였고 품질 지표에도 부정적인 영향을 주지 않는 것으로 나타났다. 이러한 비열처리 펫푸드의 살균 기술 개발은 국내 펫푸드 시장의 활성화와 반려 동물의 복지 향상에 기여할 것으로 기대된다.

A survey was conducted to examine the effect of food irradiation education on college students' knowledge and acceptance of food irradiation. The instrument for the knowledge and acceptance of food irradiation was administered before and after food irradiation education, to 150 students majoring in food and nutrition or food technology in the Chungnam National University. Before the education approximately 93% of the respondents did not know that radioactivity dose not remain in food after irradiation; whereas, after education half of them thought that radioactivity dose not remain in irradiated food. Knowledge about food irradiation has improved through education. The education significantly increased all the mean scores of need for food irradiation and willingness to use irradiated foods for the six food groups (p<0.01). The education significantly decreased the mean scores of concern about the irradiated food for all the six food groups (p<0.01). Although the responses to irradiated foods are, in general, negative or neutral even after education, the mean scores of acceptance of the irradiated foods have improved through education in all the six food groups (p<0.01). In conclusion, this study showed that food irradiation education may positively affect the college students' knowledge and acceptance of food irradiation, and that the development of both the appropriate detection methods to identify irradiated foods and the education programs to enlighten the college students are needed.

A survey was conducted to examine the knowledge and acceptance of food irradiation in order to provide baseline data required in the development of food irradiation education programs for college students. 150 students majoring in food and nutrition or food technology in the Chungnam National University were chosen for a survey. The results are as follows. First, college students' knowledge about food irradiation is scanty. Knowledge assessment showed that 56% of the participants had previously heard of food irradiation. 68% of the respondents thought that radioactivity remains in food after irradiation and 25.3% of them were not sure whether radioactivity remains in food after irradiation or not. Only half of the respondents thought that nutrient loss due to irradiation is equal to or lower than that due to cooking or freezing. Second, approximately 56% of the respondents showed that food irradiation is somewhat or strongly needed for meat or fish; whereas, over 60% of them showed that food irradiation is not needed for grain, vegetable and fruit. Almost 40% of the respondents were seriously concerned about irradiation of vegetables and fruits; whereas, they showed less concern about spice irradiation. More than half of the respondents were not willing to use irradiated food in all the six food groups. Third, the correlation analysis showed that the need of food irradiation is negatively correlated with concerning about the irradiated fish and fruits, but positively correlated with willingness to use irradiated food in all the five food groups, except in spices. Concern about the irradiated food is negatively correlated with willingness to use irradiated food from all the six food groups. Fourth, almost all the respondents (over 90%) agreed that the irradiated food labeling is required as well as the development of proper methods to identify irradiated foods.

Food irradiation is an emerging technology which offers many advantages such as reduction of microorganisms, extension of shelf-life of foods, reduction in the use of post-harvest chemicals, and destruction of insects and parasites. The commercial utilization of food irradiation, however, has been restricted because of the uncertainty of consumers' responses to it. Because success of food irradiation in the marketplace will depend upon their acceptability by consumers, this study focused on the consumers' perception and acceptance toward food irradiation in order to get basic data for commercial utilization of food irradiation and give information to consumers to help rational consumption behavior. The survey with 411 respondents living in Youngnam area was conducted during the spring of 1997 by the questionnaires. The results and implications from this study are as follows. First, consumers' knowledge about food irradiation is scanty. Two-thirds of respondents in the survey had not heard of irradiated foods and many people confused irradiation with radioactivity. In the willingness to accept food irradiation, one-third of respondents showed a wait-and-see attitude. This result indicated consumers had insufficient information about the irradiation process and nationwide education of food irradiation technology should be undertaken. Second, although the purchase and use of food are very important consumption behaviors, consumer education by mass communication has been rarely done. For the successful commercialization of food irradiation, the information provision by mass communication for the consumers should be made. Third, consumers generally worried about residual pesticide and intended to purchase irradiated foods if radioactivity was not retained in the foods. Therefore, food irradiation could be an alternative method to the use of pesticide Fourth, consumers pointed out that they wanted to extend shelf-life of milk and dairy foods, fish and seafood and to irradiate these foods. Therefore, research for the safety of irradiated foods should be continually conducted. finally, labeling for irradiated foods is needed to provide the information and to further increase public understanding. Especially, the labeling should show the definite reason why irradiation is being used. In conclusion, recently, under the circumstances that the commercial utilization of food irradiation and irradiation for the import and export products have been increased in many countries, many efforts are needed to improve the quality of irradiated foods, and prove the safety of them in Korea. In addition, consumer education for food irradiation should be given to help consumers to make decision for food purchase and use.

본 연구는 환자용 균형영양식으로 제조하여 감마선 조사처리를 통해 살균한 모델식품의 유전독성 여부를 평가하기 위해 수행되었다. 4 kGy 이상의 흡수선량으로 감마선 조사처리한 시료에서 생균수가 1 log CFU/g의 검출한계 이하로 나타났기 때문에 살균을 위한 조사처리 선량으로 4 kGy를 설정하였다. 복귀돌연변이 유발성 평가 결과, 모델식품의 열수 추출물과 메탄올 추출물은 처리한 용량과 대사활성계존재 여부와는 상관없이 음성대조구(멸균증류수 또는 DMSO)와 유사한 수준의 복귀돌연변이 발생빈도를 나타내었다. 염색체 이상 시험에서 실험군들의 정상 염색체의 수는 음성대조군과 유사하였으며, 용량 및 대사활성계에 대한 비의존성을 나타내어 염색체 이상 유발능은 없는 것으로 판단하였다. 또한 최고 2,000 mg/kg 체중의 농도로 모델식품을 경구 투여한 마우스의 골수세포에서도 소핵 다염성적 혈구의 발생빈도는 음성대조군에 비해 유의적인 차이를 나타내지 않았다. 따라서 4 kGy의 흡수선량으로 감마선 조사처리한 환자용 균형영양식은 본 실험 조건하에서 유전독성을 나타내지 않는 것으로 사료된다.

가공식품과 화장품 산업에 사용되는 식용색소의 감마선 조사로 인한 이화학적 특성 변화를 연구할 목적으로 기계적 색도 변화를 측정하였다. 적색 2호(Amaranth), 녹색 3호(Fast Green PE), 청색 2호(Indigo Carmine)용액을 0.01 및 의 농도로 준비하였으며, 0.25, 0.5, 1 및 3 kGy로 조사를 실시하여 기계적 색도 (L, a, b, )를 측정하였다. 감마선 조사는 농도 시료의 색소에 영향을 미쳤으며, 전반적인