It actually doesn't matter—here's the simple explanation for aluminum foil and the difference between its shiny and not shiny side appearances.
You're using tin foil wrong - Lifestyle News - NZ Herald
Uncle Bugs: How to use the aluminium foil correctly
Shiny vs. Dull Side of Foil: Which Should You Use?
Aluminum Foil Which Side Should You Use?
Sausage and Veggie Foil Packet Dinner for Camping - The Home Intent
Aluminum Foil: Should the Shiny Side be Up or Down When Cooking?
Aluminum Foil Which Side Should You Use?
Why does aluminium foil have a shiny and a dull side?
Can You Use Aluminum Foil in an Air Fryer? - Southern Home Express
These Aluminum Foil Uses Are Not Advised
The Mystery of the Shiny vs. Dull Side of Aluminum Foil
Chef Tom Kerridge claims that foil should be 'shiny side down' - but do YOU think he's right?
Is Aluminum Foil Toxic When Cooking? Food-Safety Experts Explain
Washington County Health and Human Services - Cover cardboard with aluminum foil (shiny side out) and place it in your sun-facing windows. This will reflect heat and make your home a little