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

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

“I thought they were making sour mash to drop on the Germans, get them all drunk,” he said.

From New York Times

Becton suggested that more stringent age and storage requirements could apply to specific categories like “Tennessee straight whiskey” or “Tennessee sour mash whiskey.”

From Washington Times