An overview of the Salmonella enteritidis risk assessment for shell eggs and egg products.

This article summarizes a quantitative microbial risk assessment designed to characterize the public health impact of consumption of shell eggs and egg products contaminated with Salmonella Enteritidis (SE). This risk assessment's objectives were to: (1) establish the baseline risk of foodborne illness from SE, (2) identify and evaluate potential risk mitigation strategies, and (3) identify data gaps related to future research efforts. The risk assessment model has five modules. The Egg Production module estimates the number of eggs produced that are SE-contaminated. Shell Egg Processing, Egg Products Processing, and Preparation & Consumption modules estimate the increase or decrease in the numbers of SE organisms in eggs or egg products as they pass through storage, transportation, processing, and preparation. A Public Health Outcomes module then calculates the incidence of illnesses and four clinical outcomes, as well as the cases of reactive arthritis associated with SE infection following consumption. The baseline model estimates an average production of 2.3 million SE-contaminated shell eggs/year of the estimated 69 billion produced annually and predicts an average of 661,633, human illnesses per year from consumption of these eggs. The model estimates approximately 94% of these cases recover without medical care, 5% visit a physician, an additional 0.5% are hospitalized, and 0.05% result in death. The contribution of SE from commercially pasteurized egg products was estimated to be negligible. Five mitigation scenarios were selected for comparison of their individual and combined effects on the number of human illnesses. Results suggest that mitigation in only one segment of the farm-to-table continuum will be less effective than several applied in different segments. Key data gaps and areas for future research include the epidemiology of SE on farms, the bacteriology of SE in eggs, human behavior in food handling and preparation, and human responses to SE exposure.     

质量、信息和公共政策:消费者购买无公害鸡蛋的影响因素分析

本文以在北京市海淀区进行的消费者访谈和问卷调查,分析了消费者收入,消费者对产品的信任程度、消费者个体特征、无公害鸡蛋和普通鸡蛋的价格差等对消费者鸡蛋购买行为的影响。基于数量化理论Ⅱ类的模型估计结果表明,消费者的收入水平、对无公害鸡蛋的相信程度以及性别是影响消费者购买无公害和绿色鸡蛋的主要因素,而年龄和不同地点无公害鸡蛋与普通鸡蛋的价格差对消费者购买行为的影响比较复杂,教育程度对购买行为的影响较小,但其影响方向与理论预期一致。根据实证结论,最后提出了提高中低收入者的收入水平、通过政府监控宣传和生产者的自律提高消费者对无公害食品的信任程度、以及将无公害鸡蛋价格的合理设定等政策含义和商业启示。     

Consumer-Phase Salmonella enterica serovar Enteritidis Risk Assessment for Egg-Containing Food Products

We describe a one-dimensional probabilistic model of the role of domestic food handling behaviors on salmonellosis risk associated with the consumption of eggs and egg-containing foods. Six categories of egg-containing foods were defined based on the amount of egg contained in the food, whether eggs are pooled, and the degree of cooking practiced by consumers. We used bootstrap simulation to quantify uncertainty in risk estimates due to sampling error, and sensitivity analysis to identify key sources of variability and uncertainty in the model. Because of typical model characteristics such as nonlinearity, interaction between inputs, thresholds, and saturation points, Sobol's method, a novel sensitivity analysis approach, was used to identify key sources of variability. Based on the mean probability of illness, examples of foods from the food categories ranked from most to least risk of illness were: (1) home-made salad dressings/ice cream; (2) fried eggs/boiled eggs; (3) omelettes; and (4) baked foods/breads. For food categories that may include uncooked eggs (e.g., home-made salad dressings/ice cream), consumer handling conditions such as storage time and temperature after food preparation were the key sources of variability. In contrast, for food categories associated with undercooked eggs (e.g., fried/soft-boiled eggs), the initial level of Salmonella contamination and the log10 reduction due to cooking were the key sources of variability. Important sources of uncertainty varied with both the risk percentile and the food category under consideration. This work adds to previous risk assessments focused on egg production and storage practices, and provides a science-based approach to inform consumer risk communications regarding safe egg handling practices.     

纸膜成型无铅松花蛋的研制

在松花蛋形成原理基础上 ,利用有效的辅助材料和纸膜技术 ,经过配方筛选 ,对纸膜加工松花蛋的碱液的浓度、形成时间、感官指标等方面进行试验探索 ,为工厂化生产提供依据。     

鲤鱼胚胎冷却至-196℃的试验

鱼类胚胎的低温保存是世界范围内尚未解决的课题,在对鲤鱼胚胎低温保存的初步试验中,我们发现在溶液冰点至-60℃范围内,降温速率对胚胎存活率来说是个决定性因素。如降温速率大于0.5℃/min,胚胎很难存活,而最佳降温速率应小于0.07℃/min,对于鱼类胚胎保存而言,慢复温是比较合适的。在我们的试验研究中,若以2.0mol/LDMSO为抗冻剂,降温速率为0.07℃/min,复温速率为8℃/min时,兴国紅鲤尾芽期胚胎经降温至液氮温度(-196℃),并保存一段时间后复温,仍能存活并孵化为幼鱼。试验达到的最大存活率为25%,出苗率为18%。     

中子辐照刺激卤虫卵孵化技术研究

用14MeV快中子低剂量辐照刺激休眠卤虫卵筛选出最佳辐照剂量和辐照时间、经过大量的实验室试验及生产中试,结果表明,辐照组比对照组的卤虫卵孵化率平均提高了17%.     

壳聚糖制取及其应用的研究

探讨从虾壳中提取甲壳素、壳聚糖的工艺,发现虾壳浸取方式直接影响产品质量,采用酸碱交替浸泡较好;用50％NaOH溶液脱除甲壳素中的乙酰基则只有在温度大于105℃时,才有可能在3小时内脱除80％以上,并提出了碱液套用的方法,可降低成本70％以上。还发现1％壳聚糖的1％醋酸溶液对香蕉有显著的保鲜效果。     

种蛋保存过程中几种因素对孵化率的影响

本文就种蛋保存时间长短和在保存期间翻蛋与否及三种放置方式对孵化率的影响进行了试验，结果表明种蛋在保存期间不翻蛋组的孵化率高于翻蛋组，不同的放置方式对孵化率没有影响，种蛋保存时间愈短孵化率愈高     

市售松花蛋中重金属铅的含量的测定

在海南某县一农贸市场对市售松花蛋(皮蛋)随机取样,在实验选定适合的测定条件下,通过原子吸收光谱法分析市售松花蛋重金属铅(pb)的含量。分析结果表明,在该农贸市场销售的松花蛋中,重金属铅的含量普遍高于国家标准。长期食用铅含量超标的松花蛋会对人体产生严重危害,文章建议食品安全部门加强对农贸市场销售的松花蛋进行技术监督,保证市售松花蛋符合国家标准,确保人民群众生命健康不受伤害。本文在食品技术监督和食品卫生安全管理等方面具有一定的指导意义。     

Organic coasts? Regulatory challenges of certifying integrated shrimp–mangrove production systems in Vietnam

The Vietnamese government aims to expand the scale of Naturland certified organic production in integrated shrimp–mangrove farming systems across the coast of Ca Mau province by 2015. In doing so the division between public and private regulation has become blurred. We analyze the government's goal by examining the regulatory challenges of using organic certification as a means of linking farm-level management to the sustainability of coastal (mangrove) landscapes. The results show the importance of farmer perceptions of sustainable farm and landscape management, fair benefit sharing mechanisms in the certified value chain, and legitimate private sector-led auditing. We conclude that in order to overcome conflicts of interest and legitimate representation in organic certification, the social and economic conditions of production require regulatory intervention from provincial and local level government. To achieve benefits beyond the scale of the farm, the role of shrimp producers should be redefined as partners in rather than targets of regulation.