Yorkshire Square

A Yorkshire Square is a traditional fermentation vessel used in brewing, especially for brewing certain ales like traditional British ales. It consists of a rectangular or square wooden or metal box with a sealed lid, fitted with a valve at the top. During fermentation, yeast converts sugars into alcohol and carbon dioxide, producing pressure that causes the foam to escape through the valve—keeping oxygen out and reducing contamination. This method allows for controlled fermentation, often with natural temperature regulation, and can enhance the beer's flavor profile while minimizing the need for extensive cleaning of the vessel.