I’m guessing that peel and rind are basically synonyms, since the dictionaries I’m checking seem to use approximately the same definition for each of them.
Is there any technical botanical (or culinary) difference between a peel and a rind?
Peels are thin. (apple, grape)
Rinds are thick. (orange, watermelon)
I don’t believe there is any technical distinction.
Peel is the more general term, and can apply to both thin-skinned and thick skinned fruits.
However, thin peels that cannot easily be removed by hand are usually just called skins (apple, pear, peach, etc.)
Rind is more restricted, and applies to thicker, harder peels (orange and other citrus, melon).
Peel does tend to be used mostly for coverings that can easily be removed by hand (orange, banana), and would not be applied to something like a melon rind.
It also depends on the context. To a bartender, an orange has both a peel and a rind. The peel is the orange outer layer (garnish for drinks, possesses essential fragrant oils). The rind is the bitter white inner part of the covering of the fruit.
Interesting about bartenders – cooks would call those elements the zest (colorful outer layer) and the pith (bitter inner layer). Which I believe is the technical distinction, but of course context is everything in these circumstances.
It was citrus fruits that got me thinking about this – I’ve heard them described both as orange rinds and orange peels, and I wondered if either was technically correct, or if peels were a subcategory of rinds (or vice versa), or if there’s no real distinction beyond common sense (cantaloupes don’t have peels, but do have rinds).
The OED defines a rind as a peel or skin, and a peel as a rind or skin.
That just shows that the OED is not attempting to give find distinctions of meaning. In this case, the words are clearly not synonymous, and differences exist in practice. No one speaks of watermelon peels, or of apple or banana rinds.
I think it’s purely a question of idiom. It’s idiomatically correct to say watermelon rind and apple peel, for instance. But if you try to nail things down on the basis of whether you remove it by hand, or how thick it is, you’ll never get anywhere.
What does one calls the outside of a pineapple, by the way? You neither peel a pineapple, nor take the rind off, but by God, whatever that outer stuff is, you’ve got to get it off.
True, but as Sal Ammoniac points out, it’s a question of usage, not definition.
Google terms up slightly more hits for “pineapple skin” than “pineapple rind” – for whatever that’s worth.