Maio Rita, García-Díez Juan, Saraiva Cristina
Department of Veterinary Sciences, School of Agrarian and Veterinary Sciences, University of Trás-os-Montes e Alto Douro, Quinta de Prados, 5001-801 Vila Real, Portugal.
CECAV-Animal and Veterinary Research Centre, University of Trás-os-Montes e Alto Douro, Quinta de Prados, 5001-801 Vila Real, Portugal.
Foods. 2020 Jul 13;9(7):919. doi: 10.3390/foods9070919.
Currently, food waste represents an important issue due to its negative economic, social and environmental impact. To reduce the food waste levels, some retailers' brands implement discounting based on the proximity to expiry. Since this practice may involve potential food poisoning, a total of 94 food products from animal origin, purchased in two supermarkets in North Portugal on the expiry date, were analyzed for selected foodborne and spoilage microorganisms. Moreover, the samples were classified as satisfactory and not satisfactory according to their microbiological quality. The results showed that none of the samples presented counts for spp., was detected in one sample over the limit of 2 log cfu/g as defined by Regulation 2073/2005. The evaluation of food hygiene and spoilage indicators showed that the processed foods displayed lower counts than raw products (beef, pork, chicken and fish). Regarding Enterobacteriaceae, raw products presented on average over 2 log cfu/g than processed foods, with the exception of beef samples that accounted over 3 log cfu/g more than processed foods. In addition, was mainly detected in fresh meat of which chicken and pork displayed the highest counts. Regarding the qualitative classification, 51.06% of the samples were not satisfactory for the total mesophilic counts, while 62.76% and 58.51% displayed positive results for Enterobacteriaceae and molds and yeasts (M&Y) criteria, respectively. In all, 70.21% of the samples analyzed at the expiry date failed, at least, in one microbiological criterion. The results indicate that the foods available at the end of the shelf life in supermarkets do not represent a risk for food poisoning due to the absence of foodborne pathogens. Since the microbiological indicators of storage/handling of raw products were mainly unsatisfactory, this indicates that the sale of these perishable foods at the end of the shelf life may not be recommended. On the other hand, processed products subjected to food conservation procedures (i.e., thermal processing) could be sold at the end of their shelf life or donated beyond the best-before date, due to its physical, chemical and microbiological stability. However, evidences of foodborne outbreaks associated to this kind of foodstuffs indicated the need of a proper risk assessment. Moreover, it is important to remark that other factors such as small sample size, the absence of the evaluation of the handling, and storage conditions along the food chain or organoleptic alterations must be assessed in further studies.
目前，食物浪费因其负面的经济、社会和环境影响而成为一个重要问题。为了降低食物浪费水平，一些零售商品牌根据保质期临近情况实施打折销售。由于这种做法可能会导致潜在的食物中毒，因此对在葡萄牙北部两家超市购买的94种动物源性食品在保质期当天进行了分析，检测其中选定的食源性病原体和腐败微生物。此外，根据微生物质量将样本分为合格和不合格两类。结果表明，没有一个样本的 spp. 计数超标，仅一个样本中的 检测结果超过了欧盟法规2073/2005规定的2 log cfu/g的限量。食品卫生和腐败指标的评估表明，加工食品的菌数低于生鲜产品（牛肉、猪肉、鸡肉和鱼肉）。关于肠杆菌科，除牛肉样本的菌数比加工食品高出3 log cfu/g以上外，生鲜产品的肠杆菌科平均菌数比加工食品高出2 log cfu/g以上。此外， 主要在鲜肉中检测到，其中鸡肉和猪肉的菌数最高。在定性分类方面，51.06%的样本总嗜温菌数不合格，而分别有62.76%和58.51%的样本肠杆菌科以及霉菌和酵母菌（M&Y）标准检测呈阳性。总体而言，在保质期当天分析的样本中，70.21%至少在一项微生物标准上不合格。结果表明，超市货架期结束时的食品由于不存在食源性病原体，不会造成食物中毒风险。由于生鲜产品储存/处理的微生物指标大多不合格，这表明不建议在保质期结束时销售这些易腐食品。另一方面，经过食品保存程序（即热处理）的加工产品因其物理、化学和微生物稳定性，可以在保质期结束时销售或在最佳食用日期之后捐赠。然而，与这类食品相关的食源性疾病暴发事件表明需要进行适当的风险评估。此外，必须指出，其他因素，如样本量小、未评估食品链中的处理和储存条件或感官变化等，需要在进一步研究中进行评估。
