Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Torino, Italy.
Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Torino, Italy.
Int J Food Microbiol. 2020 Sep 2;328:108661. doi: 10.1016/j.ijfoodmicro.2020.108661. Epub 2020 May 15.
Virus detection in food requires appropriate elution and concentration techniques which need to be adapted for different food matrices. ISO/TS-15216-1:2017 and ISO/TS-15216-2:2019 describe standard methods for hepatitis A virus (HAV) research in some food only. Milk-based products containing one or more types of fruit are not covered by ISO procedures, even though they can be contaminated by fruit added to these products or by the food handlers. The aim of this work was to identify an efficient method for the detection of HAV in milk-based products. Four methods were tested to recover HAV from artificially contaminated milk, yoghurt and ice cream containing soft fruits. Results showed that the efficiency of the tested methods depends on the analyzed matrix. In milk we obtained a mean recovery from 13.4% to 1.9%; method based on high speed centrifuge gave the best values. The average recovery in yoghurt was between 3.3% and 114.4%, the latter value achieved by method with beef extract at 3% as eluent. Finally, two methods gave the best results in ice cream with similar recoveries: 29.1% and 27.7% respectively. The first method used glycine as eluent while the other one was based on high speed centrifugation. The ISO method has never proved to be the most efficient in the matrices studied. Therefore, based on the results obtained, a complete rethinking of the ISO method may be necessary to improve its recovery for some products such as milk, while only small changes would be sufficient for other products, such as yoghurt and ice cream.
食品中的病毒检测需要适当的洗脱和浓缩技术，这些技术需要针对不同的食品基质进行调整。ISO/TS-15216-1:2017 和 ISO/TS-15216-2:2019 仅描述了甲型肝炎病毒（HAV）在某些食品中研究的标准方法。含一种或多种水果的乳基产品不受 ISO 程序涵盖，即使它们可能被添加到这些产品中的水果或食品处理者污染。本工作的目的是确定一种从乳基产品中检测 HAV 的有效方法。测试了四种方法从人工污染的牛奶、酸奶和含软水果的冰淇淋中回收 HAV。结果表明，测试方法的效率取决于分析的基质。在牛奶中，我们得到了从 13.4%到 1.9%的平均回收率；基于高速离心的方法给出了最佳值。酸奶中的平均回收率在 3.3%至 114.4%之间，后者是用 3%牛肉提取物作为洗脱液的方法获得的。最后，两种方法在冰淇淋中给出了最佳结果，回收率相似：分别为 29.1%和 27.7%。第一种方法使用甘氨酸作为洗脱液，另一种方法基于高速离心。在研究的基质中，ISO 方法从未被证明是最有效的。因此，根据获得的结果，可能需要对 ISO 方法进行全面重新思考，以提高其对某些产品（如牛奶）的回收率，而对其他产品（如酸奶和冰淇淋）只需进行微小的更改。
