§ 311.20 Sexual odor of swine.
(a) Carcasses of swine which give off a pronounced sexual odor shall be condemned.
(b) The meat of swine carcasses which give off a sexual odor less than pronounced may be passed for use in comminuted cooked meat food product or for rendering. Otherwise it shall be condemned.
It’s called taint.
When you kill a sexually developed male pig they often release musk and sweat. So it smells like going into a room where a couple just did it.
I used to raise Blue Butts (variety of pig) and have the butcher come once a year after auction to cut them up. The Musk smell isn’t that bad unless done in an enclosed area.