Sour beer has been super popular lately, especially since summer weather has hit. These beers tend to be less hoppy and more tart.
At Signal Brewing Company, all of the sour beer we've made so far is the result of kettle souring. This includes the Cherry, Blackberry Vanilla, Kiwi and Strawberry Rhubarb Volt flavours.
A kettle sour is a quick souring. We mash and make sweet wort as usual, but instead of boiling it and adding hops right away we add seven different strains of lactobacillus, a souring bacteria, and allow them to create lactic acid over a few days. Once the wort is soured to our liking, we boil it, add a little hops and finish it as a normal beer would be brewed. In the future, we plan on creating some sour beers that will focus less on lactic acid and more on some radical souring methods.