How do I know if my food has been stored in high-grade or low-grade aluminum foils?

Determining the grade of aluminum foil used for food storage can be challenging without specific testing. High-grade aluminum foils are typically thicker, more resistant to tearing, and have a brighter, shinier appearance. They also conduct heat more evenly, which can be beneficial for cooking. Low-grade foils are thinner, may be more prone to tearing, and have a duller finish. They may also have impurities or inconsistencies that can affect food safety. However, the safest way to ensure the quality of aluminum foil is to purchase from reputable brands and check for any certifications or quality marks on the packaging. Avoid using foil that shows signs of wear, discoloration, or has an odd smell, as these could indicate low-grade or compromised material.