Don't use aluminum baking sheets.
Specifically THOSE sheets.
If they are shaving off, then they are inferior aluminum or extremely cheap aluminum. I don't know of any bakery that I've ever been in that used aluminium anything, simply because they don't last, they stick to everything, and it's more of a pain having to find the RIGHT kind of aluminum to use, rather than just getting steel, ceramic, or cast iron.
You probably got them to save money, but how much food have you had to throw out because of the possibility of contamination?
If you MUST use aluminum pans, then you need to use them on something with a flat metal surface, like a pizza oven, coat them liberally with butter, grease, or non-stick coatings, or with parchment paper or wax paper, even silicone baking mats.
Aluminum is one of the WORST things you can use in a bakery. I would look for investing in a really good set of solid steel or stainless steel pans. But if you must go for aluminum, you need hard pressed aluminum, not rolled aluminum. Hard pressed aluminum is kind of like bonded steel, it lasts longer without the easy wear and tear on it. But most places use rolled or poured aluminum, so it hasn't been met with high density pressing to solidify it. Hard pressed aluminum really doesn't exist in the baking world anymore, as it is so much cheaper to use rolled or poured aluminum.