Thanks for it. I'll search for more tonight. In terms of corrosion, smooth side has fewer cracks and dents, so it is always easier to form a uniform oxide layer and trap less corrosives. But, if they use some lubricant, then there is a residue left, which can be unhealthy. They can also add something to the lubricant to form a protective film. If so, the dull side should contact food because it is cleaner.
I will definitely search for more tonight.
