Less plastic, more tea: active food packaging

该研究旨在解决当前的全球塑料废物危机，包括微塑料海洋污染问题沿着减少食物浪费和食源性疾病的发生。最近，消费者的需求不仅转向延长保质期的新鲜食品，还转向天然包装材料，以减少其对环境的影响。生物聚合物应该能够在自然堆肥条件下降解，并与天然抗微生物剂或抗氧化剂结合形成“活性包装”。这种活性包装的好处包括：延长保质期，从而减少食物浪费，减少食源性细菌和其他微生物对食物的降解，以及包装在其寿命结束时的生物降解性。该研究将涉及开发一种可生物降解的包装材料，并封装活性剂（如绿色茶中的多酚），该活性剂应以受控方式释放。这种控制释放将通过在第一种情况下使用PLA纳米颗粒来包封活性剂来探索。总之，这将形成用于延长食品保质期和防止腐败的“活性包装”。随着项目的进展，将在模型系统和实际食品上测试微生物的抑制作用。重要的因素将包括活性（抗氧化剂或抗微生物）剂的封装、该剂向食品和/或包装的顶部空间的受控释放以及包装本身的生物降解性。这项工作将开始测试天然抗菌剂，如绿色茶提取物。天然成分是有益的，因为它们具有固有的生物相容性，消费者的接受程度通常取决于包装不含非天然物质。该合成技术和程序可以随后应用于水过滤膜以防止生物污染，沿着其他潜在的医疗保健应用。

This research aims to address the current global plastic waste crisis including issues with microplastic ocean pollution along with the reduction of both food waste and the occurrence of food borne diseases. Consumer demands have recently moved towards not only fresh foods with extended shelf life, but also natural packaging materials in an effort to reduce their environmental footprint. The biopolymers should be able to degrade under natural composting conditions and be combined with natural antimicrobial or antioxidants to form "active packaging". The benefits of this active packaging include; extended shelf life and hence reduced food waste, the reduction of food degradation by foodborne bacteria and other microbes, and the biodegradability of the packaging in its end-of-life scenario. The research will involve developing a packaging material which is biodegradable and encapsulates an active agent (such as a polyphenol from green tea), which should be released in a controlled manner. This controlled release will be explored through the use of PLA nanoparticles in the first instance to encapsulate an active agent. Together, this will form 'active packaging' used to prolong the shelf-life of food and to prevent spoilage. The inhibition of microbes will be tested both on model systems and actual food as the project progresses. Important factors will include the encapsulation of the active (antioxidant or antimicrobial) agent, the controlled release of this agent to the food and/or headspace of the packaging, and the biodegradability of the packaging itself. The work will begin by testing natural antimicrobial agents such as green tea extract. Natural components are beneficial as they are inherently bio-compatible and consumer acceptance will often rely on the packaging being free of non-natural agents. The synthesis technique and procedure could later applied to water filtration membranes to prevent biofouling, along with other potential applications in healthcare.