Whiskey Barrel Sour Lime Recipe

It's summer and it's hot and I love whiskey and I love limes, so this seems like a natural mashup for me. There are essentially no breweries making this style of beer at the moment that I can track down. I found some tequila barrel-aged lime ale, but that's not what I'm shooting for. The goal is a lime flavored beer with undertones of whiskey with a subtle sour finish. Into uncharted territory I go.

This isn't my first time adding fruit to a barrel to flavor beer, so I wanted to play with the limes in a neutral base beer to evaluate them. I pitched East Coast Yeast BugFarm (ECY01), and fermented the beer in a third-use barrel from Balcones Distilling for two weeks with a blow-off tube setup. This recipe batch size is for 2.5 gallons, so I can complete primary fermentation in the barrel with plenty of head space. I reserved 2.5 gallons of a previous batch of one year aged Whiskey Wild IPA to blend into this beer also.

These 5 gallon barrels have a high surface-to-volume ratio, compared to larger volume barrels, which results in a greater amount of oak in contact with the aging beer. This is the third batch of beer to go into the barrel, so the oak character/tannins should be knocked down a few pegs for a better balance in this sour beer. Wild yeast fermentations don't leave behind much sweetness, so using a barrel that has been through a few aging runs and hot washes should help bring the oak levels down to match the sour finsh.

Another concern with small barrels is the evaporation loss and oxidation potential from permeable wood. Small barrels have thinner staves than what commercial producers of barrel aged-beers use, so I always cover the top staves and fill all gaps with barrel wax. The opportunity for oxidation increases with these thinner walls and the higher surface area beer has to oak.

I decided to use a heavier amount of 6-row than usual to get a deeper grain flavor than 2-row malt would give me alone. That was assisted by a variety of crystal, melanoidan and wheat to balance out the flavor of the whiskey.

With the primary fermentation complete, I racked the beer on 1 lb of fresh cut Key Limes dropped into another third-use 5 gallon Balcones barrel. At this point I blended in some of the the reserved Whiskey Wild IPA and added some sanitized glass marbles to fill the head space. If you don't top up the liquid in a barrel, the upper staves will dry out and allow oxidation and evaporation. For now, I leave on an airlock.

It's hard to time a sour beer, but a good rule of thumb for barrel aging is primary for two weeks (in a barrel or traditional carboy), four to six months (barrel aging), then onto fruit until ready to keg/bottle. Below is a 2.75 gallon recipe, but you can adjust accordingly in your brewing software.

Christian Lavender is a father, husband, computer geek, beer writer and homebrewer in Austin, TX. He currently brews on Picobrew's Zymatic and enjoys styles ranging from hoppy barrel aged barley wine to funky sours. Follow Christian's brewing on