Understanding the Mystery of Aluminum Foil
The question of whether to use the shiny or dull side of aluminum foil when cooking has long been a topic of debate among home cooks. Many have wondered if one side is better than the other for preventing food from sticking, especially when reheating pizza slices or baking fish. However, the truth might surprise you.
Is There a “Correct” Side?
For those who are concerned about their cooking methods, it’s reassuring to know that there is no definitive right or wrong side to use when cooking with aluminum foil. According to the USDA, both sides are equally effective at heating food. This means that choosing one side over the other won’t ruin your meal. So, feel free to pick whichever side you prefer—there’s no need to worry about making a cooking mistake.
Why Does Aluminum Foil Have Two Sides?
If both sides are equally functional, then why does aluminum foil have a shiny and a dull side in the first place? The answer lies in the manufacturing process. Experts at Reynolds Kitchens explain that the difference between the two sides is due to a process called milling. During this process, heat and tension are applied to stretch and shape the foil. Two layers of foil are pressed together and milled simultaneously, which helps prevent the foil from breaking.
“Where the foil is in contact with another layer, that’s the ‘dull’ side,” Reynolds explains. “The ‘shiny’ side is the side milled without being in contact with another sheet of metal. The performance of the foil is the same, whichever side you use.”
Choosing the Right Side for Non-Stick Foil
While standard aluminum foil doesn’t make a difference in terms of performance, there is a distinction when using non-stick foil. In this case, the non-stick coating is only applied to the dull side. Therefore, it’s recommended to use the dull side when cooking with non-stick foil. Most non-stick foils will have a label indicating the non-stick side, so you won’t have to guess.
Foods That Should Be Avoided When Using Aluminum Foil
Although aluminum foil is convenient, there are some foods that should be cooked without it. A small amount of aluminum can leach into food, especially when cooking animal-based proteins. A 2019 study published in Food Science & Nutrition found that salmon, mackerel, and duck breast absorbed the most aluminum when baked at 425° F for 40 minutes. In 2020, Italian researchers discovered that aluminum made its way into beef, chicken, and fish cooked at 180° C (356° F) for an hour.
While there’s no need to panic, those concerned about aluminum intake may want to avoid using foil when preparing meats at high temperatures. Instead, consider using a stainless steel baking sheet or roasting pan.
Trusting the Information
At Reader’s Digest, we are committed to providing high-quality content by writers with expertise and experience in their field. We consult relevant, qualified experts and rely on reputable primary sources, including government and professional organizations as well as academic institutions. All facts and data are verified, backed with credible sourcing, and revisited over time to ensure accuracy.
Sources
- USDA: “How is aluminum foil made?”
- Reynolds Kitchens: “Heavy Duty Aluminum Foil”
- Reynolds Kitchens: “Non-Stick Foil”
- Food Science & Nutrition: “Aluminum contamination of food during culinary preparation: Case study with aluminum foil and consumers’ preferences”
- International Journal of Environmental Research and Public Health: “Quantification of the Aluminum Content Leached into Foods Baked Using Aluminum Foil”
