What is a coolship used for?

Answered by Christopher Steppe

A coolship is an incredible vessel that plays a vital role in the process. Its purpose is to cool down the wort, which is the liquid extracted from malted grains, before it undergoes fermentation. This cooling process is crucial because it sets the stage for a unique and fascinating method of brewing known as spontaneous fermentation.

Spontaneous fermentation is a method of brewing that involves allowing the wort to come into contact with the surrounding environment, specifically the air, to naturally capture and cultivate wild and bacteria. The coolship facilitates this process by providing a large, open space for the wort to cool down, while also exposing it to the microorganisms present in the air.

The size of a coolship can vary, but it is typically quite large to accommodate a significant volume of wort. Its design is simple yet effective, consisting of a shallow vessel with a wide surface area. This allows for rapid cooling of the wort as it is spread out thinly, maximizing the contact with the air.

The use of a coolship dates back centuries and has its roots in traditional brewing practices, particularly in Belgium. I personally find it fascinating to think about the history and evolution of beer brewing, and the coolship is a testament to the ingenuity and resourcefulness of brewers in the past.

When the hot wort is transferred into the coolship, it is exposed to the open air, which is teeming with a variety of microorganisms. These can include wild yeast strains such as Saccharomyces, Brettanomyces, or even bacteria like Lactobacillus and Pediococcus. These microorganisms are naturally present in the environment and can settle on the wort, leading to the fermentation process.

As the wort cools down, the wild yeasts and bacteria present in the air begin to inoculate it. This means that they start to grow and multiply, converting the sugars in the wort into and other byproducts. The fermentation process can take anywhere from a few days to several months, depending on various factors such as temperature, the specific microorganisms present, and the desired flavor profile of the beer.

The beauty of using a coolship for spontaneous fermentation lies in the fact that it allows for the development of unique and complex flavors in the beer. The native yeasts and bacteria present in the surrounding environment contribute their own distinct characteristics to the brew, resulting in a beer that is truly reflective of its terroir.

I have had the pleasure of experiencing beers made using a coolship, and I must say, they are truly remarkable. The flavors can be incredibly diverse, ranging from tart and funky to fruity and complex. Each sip is like embarking on a sensory journey, as the beer reveals layers of flavors that have been shaped by the surrounding environment and the microorganisms at work.

A coolship is a vessel used in the brewing process to cool down the wort before fermentation. It allows for the wort to come into contact with the air, capturing wild yeasts and bacteria through spontaneous fermentation. This traditional and fascinating method of brewing results in beers with unique and complex flavors, making each sip a true adventure for the palate.