OnTap Magazine

brewcra .co.za Shop online now Over the last 15 years BrewCraft Int. has developed into one the most respected brands in the home beer brewing market and supplying to our specialised brew shops throughout the world. UNLOCK A WORLD OF BEER I like to refer to the phrase “the devil’s in the details” when I talk about brewing. And while with coolship brewing we basically throw away the brewing rulebooks, the devil remains on the bookshelf. Normally a brewer wants fresh hops, clear wort that is cooled quickly and a controlled fermentation. But with true spontaneously fermented coolship beer we rebel and throw all of these norms out the window. But we’re getting ahead of ourselves. Considering there is – as far as I am aware – only one coolship in South Africa, you might not be familiar with what it is and what it does. Put simply, a coolship is a large, open, at vessel that was traditionally used to cool down wort. Before the advent of refrigeration there was no quick way to cool wort. Wort needs to be cooled before yeast can be pitched and while brewers back then didn’t fully understand the role of yeast, they did realise that wort which was cooled more quickly would lead to a better end product. Some German and English brewers used coolships primarily to cool wort, later transferring it to closed vessels to ferment in a controlled manner. STEAM BEER Anchor Brewing in San Francisco is well known for their use of a coolship as an open fermenter to produce their Steam Beer. is beer was rst brewed in 1896 before the days of refrigeration. e wort would be transferred to the open, shallow vessel and cooled naturally by the cold air. As the hot air escaped the wort, it looked like steam, hence the name “steam beer”. e wort was then left in same vessel to ferment naturally. Although Anchor’s proprietary Steam Beer still uses open fermenters, these days the wort is cooled before it reaches the at fermentation vessel, so they no longer refer to it as a coolship. e main reason brewers prefer rapid cooling is to prevent any wild yeasts and bacteria from infecting the wort after the boiling process. Although coolships were designed as a way to cool down the wort as quickly as possible, they have long had another use. Some Belgian breweries use coolships to make lambic beer by spontaneous fermentation. In fact, most functioning coolships today are found in breweries producing lambic-style beers. Lambic is a centuries-old, complex beer style, displaying sour and often funky avours. Cantillon Brewery in Brussels, founded in 1900, is probably the most famous of all lambic brewers. ey still use the same infrastructure and most of the same equipment from when they started out. e process involves transferring hot wort from the kettle into the coolship and leaving the wort to cool overnight. During this time WHY A COOLSHIP? The term coolship is an Anglicised version of the Dutch/ Flemish word “koelschip”. The large surface area in relation to the volume enables an efficient cooling. Historically, coolships were little more than hollowed- out tree trunks and it was here that the name originated. The wooden vessels looked like ships at the time and of course, their purpose was to cool. In later years the coolships were lined with iron or copper to assist in thermal conductivity. Today most coolships are manufactured from stainless steel. However, copper coolships are still used in many Belgian breweries.