Ferments tasty brew from Thatch, Water, and Berries.
— In-game Description

The Beer Barrel is a structure that functions similar to the Preserving Bin and allows for the production of Beer Liquid by fermenting Thatch and Berries with water for 6 in-game hours. The Beer Liquid can be combined with the Water Jar to produce the Beer Jar in the Beer Barrel. The Beer Barrel can be filled with up to 1000 water and attached to an irrigation system to facilitate the continuous production of Beer Liquid.

Beer Liquid

Put it in a glass jar to drink it!