Aluminum foil is made of primary aluminum alloy and rolled by multiple processes, without harmful substances such as heavy metals. In the production process of aluminum foil, the high temperature annealing disinfection process is adopted. Therefore, the aluminum foil can contact with food safely and will not contain or facilitate the growth of bacteria. In most cases, aluminum foil does not react with food. However, a considerable number of plastic lunch boxes on the market are produced from raw materials of unknown origin, even fake materials and waste plastics, so the quality reliability is difficult to guarantee. If calcium carbonate, talcum powder, industrial paraffin and recycled waste are added into the raw materials of disposable plastic tableware, the evaporation residue (n-hexane) of the product is easy to exceed the standard. In July 2013, AQSIQ, SAIC and food and Drug Administration specially issued the notice on strengthening the supervision and management of disposable foam plastic tableware. In order to protect the environment and prevent the harm of plasticizer to society and human body, some local governments have also formulated laws and regulations to limit the use of disposable non degradable plastic tableware.
Aluminum foil has high conductivity, which can minimize the time and energy related to food processing, refrigeration and reheating. Aluminum foil has good thermal stability. In the process of processing and packaging, aluminum foil utensils can well withstand the change of temperature. Under the high and low temperature of - 20 ° C-250 ° C, the molecular structure is stable. It can be used from fast freezing to extreme baking and barbecue, during which the aluminum foil will not deform, crack, melt or burn, and will not produce harmful substances. Using aluminum foil to separate high temperature charcoal fire and smoke can avoid the carcinogen caused by food scorching. Aluminum foil lunch boxes and containers are suitable for high temperature sterilization and heat sealing. Aluminum foil lunch box containers can be diversified heating, including various ovens, ovens, anaerobic heating cabinets, steamers, steamers, microwave ovens (must be used in light wave and barbecue stalls), pressure cooker to heat food packed with aluminum foil. Related enterprises have developed supporting aluminum foil lunch box secondary heating equipment and packaging equipment, which can greatly improve the distribution efficiency of catering enterprises and ensure the quality of food. In contrast, plastic lunch boxes and containers are significantly lower in high temperature resistance than aluminum foil products. They will release harmful substances in contact with high-temperature food, water or high-temperature heating, which will affect human health. (the foam lunch box is made of polystyrene. The softening point of polystyrene is between 87 ℃ and 97 ℃. Therefore, it can not be used in the temperature environment above 80 ℃.
The disposable lunch boxes made of plastic are mainly PP polypropylene and PS polystyrene. PP is soft, and the use temperature of PP is - 6 ℃ to + 90 ℃. Foam plastic lunch boxes, which were popular in the early years, have been eliminated in the market. According to law enforcement officials, the raw materials of foamed plastic lunch boxes contain harmful substances. Once the food containing high temperature and high oil is contained, the harmful substances in the foam plastic are easy to separate out, migrate and condense on the food, and follow the food into the human body, causing damage to the human body. Moreover, the disposable lunch box made of foamed plastic is difficult to degrade and will not rot for many years. When burned, it will release a large number of harmful gases, causing serious damage to the environment. Therefore, since 2001, the production, sales and use of foamed plastic tableware have been completely prohibited in China.