Jester King Brewery (Austin, TX) will release Colour Five on Halloween. Colour Five is a blend of barrel aged sour beer with Texas blueberries.
The first attempt at this blueberry barrel aged sour beer failed in 2013. That batch was too vinegary (i.e. too much acetic acid.) The brewery decided to do something different for Colour Five.
This batch is 89% Das Uberkind, and 11% RU55. (The failed batch was all RU55 Sour Red.) The blueberries were frozen prior to refermentation to stave off acetobacter (makes acetic acid) and was allowed to ferment in stainless steel, where the brewery can push away oxygen (again, inhibiting acetobacter.) These steps (simplified for the story) helped Jester King bring Colour Five to fruition.
Jester King Colour Five will be available when the brewery opens at 4pm. By the glass, or 500ml bottles. ($16)