When making homemade wine, it is the smell caused by buildup of C02 from fermented fruit.
"Hey man, we need to check the wine for build up."

"Dude that shit smells like a rhino fart."


You may smell a something akin to a "Rhino Fart" Don't worry. It will dissipate in time.
http://www.instructables.com/id/S700YGMFEQ4B0S0/
by Brian Teal2 November 24, 2008
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