Well, this is a pretty literate response to a post about black tar rotgut.
From the economist.com
It was blistered by the summer sun, warmed in winter by rotgut whiskey.
From the chron.com
In fact, I'll personally guarantee you that it was pretty rotgut stuff.
From the smh.com.au
As the taster pointed out, a lot of people remember it as rotgut.
From the npr.org
They sound like Hollywood moguls swearing off R-rated rotgut for the 12-step program of PG uplift.
From the time.com
So while you don't need to spend a fortune, skip the rotgut.
From the stltoday.com
Funky label or not, that local rotgut is a hoot when you're in country, undrinkable everywhere else.
From the us.cnn.com
Make sure your vodka isn't complete rotgut.
From the theatlantic.com
For a Pennsylvanian who wants a good bottle of wine or a cheap bottle of rotgut, there remains only one place to go.
From the post-gazette.com
More examples
Any alcoholic beverage of inferior quality
Fusel alcohols, also sometimes called fusel oils, or potato oil in Europe, are higher-order alcohols (that is, alcohols with more than two carbon atoms) formed by fermentation and present in cider, mead, beer, wine, and spirits to varying degrees.