How does the moisture-proof property of aluminum foil help keep food fresh?

Aluminum foil is a thin sheet made of aluminum metal with a tight molecular structure and extremely low air permeability. This property makes aluminum foil an excellent moisture-proof material that can effectively block the penetration of external water vapor and other humid substances. The moisture-proof property of aluminum foil mainly comes from its metal properties and manufacturing process, which ensures that it can provide a dry and stable environment in packaging applications.
Food is easily affected by moisture in a humid environment, resulting in soft texture, poor taste, and even microbial growth and corruption. The moisture-proof property of aluminum foil can effectively isolate external moisture and prevent food from getting damp. At the same time, aluminum foil can also reduce the contact between food and oxygen, delay the oxidation process of food, and thus maintain the freshness and nutritional value of food.
For some foods that need to maintain a certain humidity, the moisture-proof property of aluminum foil can maintain the moisture balance inside the food to a certain extent and prevent moisture from being lost too quickly. This helps to maintain the taste and flavor of food and extend its shelf life. A humid environment is an ideal condition for the growth and reproduction of microorganisms. Aluminum foil can create an environment that is not conducive to the growth of microorganisms through its moisture-proof properties, thereby reducing the risk of food spoilage. This helps to maintain the hygiene and safety of food.
Foods such as meat and seafood are prone to moisture and deterioration. Using aluminum foil bags or aluminum foil boxes to package these foods can effectively isolate air and moisture, maintaining their fresh taste and nutritional value. At the same time, aluminum foil can also prevent food from producing ice crystals during refrigeration or freezing, which affects the taste.
Fruits and vegetables are prone to mold and deterioration in a humid environment. The moisture-proof properties of aluminum foil bags can keep fruits and vegetables dry and extend their shelf life. For fruits and vegetables that need to maintain a certain humidity, some moisturizing materials can be placed in the aluminum foil packaging to maintain the moisture balance inside the food.
Baked foods (such as bread, biscuits, etc.) are sensitive to moisture and are easily softened by moisture. Using aluminum foil bags or aluminum foil boxes to package these foods can effectively prevent them from absorbing external moisture and maintain a crisp taste. At the same time, aluminum foil can also prevent food from being squeezed and deformed during storage.
Quick-frozen foods need to maintain a low-temperature and dry environment to prevent ice crystal formation and food deterioration. The moisture-proof property of aluminum foil bags can keep quick-frozen foods dry and reduce the formation of ice crystals, thereby extending their shelf life and taste.
When using aluminum foil packaging, ensure that the packaging opening is well sealed to prevent moisture from entering from the packaging opening. Tools such as clips and tapes can be used to strengthen the sealing effect. Although aluminum foil has good moisture-proof properties, long-term exposure to high temperature or humid environments may still affect its performance. Therefore, when using aluminum foil packaging, avoid placing it in a high temperature or humid environment for a long time.
When cooking or heating food, if the food is directly wrapped in aluminum foil, ensure that the aluminum foil is not in direct contact with the food to avoid aluminum elements migrating into the food. You can choose to place the food on a baking tray or grill and then cover it with aluminum foil to maintain temperature or prevent oil splashing.