The packaging bags all say retort aluminum foil bags. Why use aluminum foil bags as retort bags? In the selection of high-temperature cooking bags, the first raw material is aluminum foil. Why can aluminum foil bags be used in high-temperature cooking? In other words, what are the advantages of aluminum foil bags in high-temperature cooking? The aluminum foil bag has good sealing properties and strong barrier properties. Aluminum foil has fewer pinholes. The aluminum foil bag ensures the food hygiene and safety level, its surface cleanliness must be high, there is no oil stains and floating dust, and the surface supporting force must be high. A simple method is to check with pure water, which should flow on the surface of the aluminum foil. The oil stains on the surface of the aluminum foil are not optimistic, which will affect the composite color fastness of the aluminum foil and other raw materials. Therefore, the composite packaging bag containing aluminum foil has the functions of sealing, high fragrance retention, conditioner oil, and high temperature resistance.