# Research and Development Status of Prepared Foods in China: A Review
## 6 Sterilization and Packaging of Prepared Foods
### Packaging and Storage Technology  
The packaging of prepared foods is critical to the preservation, transportation, and distribution of the product [122]. The choice of packaging for prepared foods needs to be adapted to the properties of the product itself, and different types of packaging need to be selected according to the type of raw materials and processing, preservation, and transportation conditions of prepared foods, so as to maintain the quality of the product [123]. Currently, the most widely used packaging materials on the market are plastic bags, cling film, and glass jars. For instance, dried small fish and other dry prepared foods are mostly packaged using plastic packaging bags; vegetables are mostly packed with cling film plus composite material packing boxes; glass jars are mostly used for canned yellow peaches, chilli sauce, and another ready-to-eat pre-prepared food packaging. However, new food packaging materials are suitable for minimally processed, easily prepared, and ready-to-eat \"fresh\" food products, as well as matching packaging technology, and they are still in urgent need of research and development, in order to meet the industry's high demand for prepared food packaging materials [122]. Intelligent food packaging [124] is considered a future development trend which is a new and efficient way to economize on business processes, solve safety and quality issues through the supply chain, and reduce product losses. Intelligent packaging technology can make certain adjustments to parameters such as humidity, temperature, and gas microenvironment based on changes in the environment in which the prepared food is located and takes the initiative to make targeted adjustments to product quality [125]. These packaging technologies could play a role in extending the shelf life of foods and reducing the risk of pathogens. If antimicrobial agents are added as a functional component to a starch foam substrate to prepare biodegradable packaging materials, the functional foam in the packaging material exhibits a behaviour of controlled oxygen release with a longer oxygen release period and lower initial release rate when in humid conditions. The active antimicrobial substance is encapsulated and placed in the food antimicrobial packaging film with intelligent controlled release performance [126], so it can release the antimicrobial substance according to the change of environmental pH, which has good preservation and a preservative ability for products such as soup and pork, and effectively extends the shelf life of the products [127]. Research has also shown that a significant shelf-life prolongation was obtained with 30% CO\({}_{2}\) in the package, corresponding to a 168% shelf-life increase compared to the control sample in the air. In addition, with the introduction of national environmental protection policies and social awareness of environmental protection [128], the degradability of prefabricated food packaging materials also has higher requirements. As a relatively green, safe, and non-polluting packaging material [129], biodegradable food packaging material has great potential in the field of pre-made food packaging. We apply the knowledge of physics, chemistry, and biology to improve the development of existing biodegradable materials to reduce the negative impact of materials on the environment while enhancing the functionality and adaptability of prepared food packaging materials and promoting the development of prepared food packaging in an environmentally friendly and sustainable direction [130]. However, although food packaging technology such as intelligent food packaging has many advantages, compared to some countries with more developed food industries, the research on advanced packaging technology in China is not in-depth, and the scope of application is also limited given the high cost. Preservation of prepared foods is crucial to the sensory quality and sale of prepared foods.