Shelf life and related issues are generally discussed and studied on packed foods. However, when original containers are opened by consumers or at industrial level, a sharp acceleration of product quality decay suddenly occurs. In these cases, the concept of secondary shelf life (SSL), that is the period after pack opening during which a food product maintains an acceptable quality level, should be introduced. SSL and related issues (e.g. food safety, quality, and consumer perception after pack opening) have received little attention in literature despite the possible remarkable impact on household management of opened products by consumers as well as on food industry management of raw material and semi-processed foods after opening. In this review, the SSL issues are critically discussed by focussing on possible spoilage events after pack opening, consumer and food industry perspectives on SSL, and SSL assessment process.

对于包装食品，通常会讨论和研究保质期和相关问题。但是，当消费者打开原始容器或在工业级别打开原始容器时，突然出现产品质量急剧下降的情况。在这些情况下，应引入二级保质期（SSL）的概念，即包装打开后食品保持可接受质量水平的时间段。SSL和相关问题（例如包装打开后的食品安全性，质量和消费者认知）在文献中很少受到关注，尽管这可能对消费者对打开产品的家庭管理以及对食品行业原材料和半成品的管理产生显着影响。开封后加工食品。在这篇评论中，通过重点讨论包装打开后可能发生的损坏事件来严密讨论SSL问题，