Glass and metal cans are the most common options. There is no need to elaborate on the benefits of glass—it is inherently harmless, visually appealing, and can achieve a sealed effect. Its one drawback is that it is fragile. People have always been able to invent many things, and so canning came into being. The classic example is that when you mention cookies, people immediately think of cookie tins. Canned storage allows food to be kept longer and enables people far from the place of production to enjoy it; and because it is canned, it is also convenient to transport. Another important reason is that the can itself is not easily damaged, which does a good job of ensuring food safety and also reduces unnecessary losses caused by breakage. As people's living standards improve, they pay closer attention to food. Many people worry whether tin cans affect the food and whether they affect health.
Actually, there is no need to worry—current production technology can already guarantee the safety of tin cans themselves. Iron products cannot tolerate water, corrosion, and the like, because these cause chemical reactions in the iron that affect the food. But it must be said that too many of the foods we eat contain water, acids, and alkalis, so ordinary iron cannot be used to hold them. Today, many tin boxes have an insulating coating applied on the inside, so that the food does not come into contact with the tin can, ensuring the box does not affect the food. But some people also worry whether the coating affects the food or the human body. Current manufacturers follow strict standards; all food packaging must undergo quality inspection, and all materials used must be reviewed, so this is also nothing to worry about.
