Seal area represents the most problematic part in food packaging for controlling the moisture and gas ingress and preserving product quality. Understanding the mechanism of heat sealing, which is a widely used method in flexible packaging, is critical for maintaining product quality throughout the storage and preventing food waste. Likewise, understanding the factors causing the leak formation in the seal interface helps to avoid failures and increase integrity for all seal types produced by heat sealing methods. This review looks at heat sealing and its mechanisms in flexible food packaging materials and particularly focuses on the reasons behind the encountered seal integrity problems that have a detrimental effect on food quality and shelf life. Heat sealing mechanisms, form fill seal systems and seal types were analyzed. Then, factors affecting the leak formation have been grouped as process parameters, material properties, contaminants, and further processes, which is uncharted territory in open literature. Finally, the details of these groups and their interrelationships were examined and discussed. Revealed key factors as shown in this study are expected to guide future research for understanding leak formation mechanisms in flexible food packaging.

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了解影响热封软包装食品密封完整性的因素：综述

密封区域是食品包装中最有问题的部分，用于控制水分和气体进入并保持产品质量。了解热封的机制（在软包装中被广泛使用的方法）对于在整个存储过程中保持产品质量并防止食物浪费至关重要。同样，了解在密封界面上形成泄漏的因素有助于避免故障，并提高通过热密封方法生产的所有密封类型的完整性。这篇综述着眼于柔性食品包装材料中的热封及其机理，特别着重于所遇到的密封完整性问题背后的原因，这些问题对食品质量和保质期有不利影响。分析了热密封机理，成型填充密封系统和密封类型。然后，影响泄漏形成的因素归类为工艺参数，材料特性，污染物和进一步工艺，这在公开文献中尚属未知领域。最后，研究和讨论了这些群体及其相互关系的细节。如本研究所示，揭示的关键因素有望指导未来的研究，以了解柔性食品包装中的泄漏形成机理。