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When using garlic cloves for pretty much anything, is it ever necessary to cut the slightly brown end off (that which connects to the head), or the middle out? Often times when I peel a garlic clove and cut into it I'll notice that the middle portion is slightly to moderately green and I'm always wondering if this should be discarded along with the brown end(s). If there are obvious blemishes in the garlic I'll remove those, but other than that is there a general rule of thumb?
Should one always use the whole garlic clove?