sour mash

American  

noun

1. a blended grain mash used in the distilling of some whiskeys, consisting of new mash and a portion of mash from a preceding run and yielding a high rate of lactic acid.

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sour mash British  

noun

1. a grain mash for use in distilling certain whiskeys, consisting of a mixture of new and old mash

2. any whiskey distilled from such a mash

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Etymology

Origin of sour mash

An Americanism dating back to 1880–85

Example Sentences

It’s not a single malt from a verdant Scottish glen, nor a sour mash bourbon from the hills of Tennessee.

From Washington Times

Or sour mash, the brown beverage that could be — just could be — making a comeback among young and millennial-age sippers?

From Washington Times

Like any respectable Sinatra aficionado, I’ve imbibed my share of Tennessee’s trademark sour mash whiskey.

From The Wall Street Journal

One Eight Distilling, for instance, sells an Untitled Whiskey No. 3, a Tennessee sour mash aged in the same barrel used for Vigilante's roasted Sumatra beans.

From Washington Post

So we call it bourbon, rye, sour mash and Carolina white.”

From Washington Times