Plated / Coated Steel

The plastic answer is clean - there is no polymer in the food path, which is exactly why an uncoated plated cavity beats a PTFE-lined one. The metallurgical answers are more mixed, and they differ by plating. Zinc is the clear no: NSF/ANSI 51 states flatly that galvanized and other zinc-coated materials shall not be used on surfaces intended for direct food contact, and the FDA Food Code bans galvanized metal for utensils and food-contact surfaces used with acidic food, because acid converts the zinc coating to zinc salts that the body readily absorbs. Nickel is the surprising one: the Council of Europe technical guide says nickel-plated objects are not suitable for direct contact with foodstuffs, and adds that chromium-plated food-contact articles should be tested for nickel release - which is a pointed instruction once you know what sits under the chrome. The chromium worry people arrive with is hexavalent chromium, and that is largely a plating-shop and occupational issue rather than a property of a finished part: ATSDR's occupational limits for chromates and for chromium metal differ by a factor of two hundred, and trivalent chromium is poorly absorbed by any route and is an essential nutrient in small amounts. We found no authority addressing what happens if you swallow a flake of plating, so we are not going to invent one. The defensible position is the one our ratings already take: plated steel is a good answer for oven interiors, racks and baskets that food touches briefly or indirectly, and bare stainless is the better answer for anything food sits in.

Chrome-over-nickel on steel is specified for stove tops and oven liners, so oven temperatures are inside its design envelope rather than a risk to it. Galvanizing has a service-temperature ceiling of its own, but the more relevant point is that zinc has no business on a food-contact surface at any temperature. Metal fume fever from zinc is a welding and cutting hazard, not a baking one, and it gets misapplied to ovens. Nothing here softens, off-gasses or sheds a polymer when hot, which is the whole reason we prefer it to a coated basket.

The tell that matters is what the base metal does when the coating is broken, so look at the places manufacturers do not plate well: cut edges, screw holes, spot welds and the underside of a rack. A plated part shows a duller, differently-coloured metal there under a brighter surface, while solid stainless is the same material all the way through. Corrosion looks different too. Plating failure concentrates at pores and scratches, so it appears as discrete rust pinpoints and blisters that grow outward from a spot; stainless in trouble tends to tea-stain across an area instead. A mirror-bright, perfectly uniform finish is more typical of plating than of the brushed finish most stainless kitchenware carries. A magnet is useless here, since both plated carbon steel and ferritic stainless attract one. When a spec sheet says only chrome finish or steel, ask what the base metal is, what the plating is, and whether there is a nickel underlayer - that last question is the one that tells you whether the part belongs in direct food contact.

Treat the coating as the whole product, because once it is breached the physics work against you. A noble coating over a less-noble base is electrically the wrong way round: the plating industry's own literature describes corrosion at a pore in the chromium being accelerated by the large surrounding cathode, with pitting able to progress rapidly, and the standard countermeasure is to deliberately make the chromium microporous so the damage spreads out instead of concentrating. Practically that means no abrasive pads, no caustic oven cleaner, and no leaving racks wet. Zinc is the exception that proves the rule, since it corrodes sacrificially and keeps protecting the steel through a scratch - which is why it is good on a fence and wrong in a kitchen. A plated part that has started pinpoint rusting is not restorable at home; it is a replacement.

It goes out as steel scrap and gets remelted; a few micrometres of plating does not stop that, and scrap yards do not sort it out. There is no coating to landfill separately and no microplastic story here, which puts it well ahead of a worn nonstick pan on the same question.