A review on smart active packaging systems for food preservation: Applications and future trends

A large amount of food is wasted throughout the supply chain, thus developing suitable active packaging materials can alleviate food waste and extend the shelf life. However, few active packaging can release functional molecules (e.g., thymol, eugenol, cinnamaldehyde, chlorine dioxide, sulfur dioxide, 1-methylcyclopropene, etc.) at the required time, required space, and required quality, which may lead to greatly reduced effectiveness. More seriously, the overuse of some functional molecules even threatens human health. It is vital to develop active packaging materials that can release functional molecules smartly. Smart active packaging provides a new approach to designing innovative active packaging systems due to their ability to respond to changes in the storage microenvironment. Compared with traditional active packaging, smart active packaging can better provide measures according to local conditions for achieving stimuli-responsive release. This review presented the latest advances in smart active packaging nowadays, including stimuli-responsive mechanisms and stimuli sources for designing smart active packaging systems such as pH, enzyme, humidity, temperature, and light. This review also discussed the challenges and possible solutions for further developing smart active packaging systems. Smart active packaging can achieve the on-demand release of functional molecules, which is essential to avoid the risks caused by excessive and premature release. Several novel approaches, such as material safety evaluation and response sensitivity enhancement, could be considered for further designing active packaging systems that are more suitable for real-life production requirements.