Kettle sour technique and fruit base selection

In our latest issue, Louisville’s Atrium Brewing scored a category-leading 98 for their barrel-aged stout Denny-Lou, Blend 1, and that was as good a reason as any to check in with cofounder Mark Rubenstein and head brewer Spencer Guy for some background on brewing stouts. Their proximity to some of the best distillers in the Western hemisphere informs their approach to both aging and blending, and they take the same iterative approach to building flavor in more ingredient-laden beers.

In this episode, they touch on:

• brewing flavored imperial stout as well as barrel-aged stout
• using a reiterated mash in lieu of longer boils for higher starting gravity
• building lower color stout with very low bitterness to let coffee shine
• balancing sweetness with tannins in barrel-aged stout
• blending with multiple stout threads
• the impacts of brandy and bourbon barrels
• kettle souring with a hazy IPA grain bill
• using probiotic beverages for kettle souring
• adjusting acids in the brite tank for proper fruit expression
• choosing fruit formats for clarity and quality
• spinning tanks then bench testing between each ingredient addition to confirm quantities with sensory
• constructing fruit blends and highlighting with yogurt

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