A krausened beer is a type of beer that undergoes a traditional German brewing technique known as krausening. Krausening is a natural carbonation process that was originally used by German brewers to carbonate their beers without the use of additional sugars or artificial carbonation methods.
The process of krausening involves adding a small amount of actively fermenting wort (unfermented beer) to the finished beer. This wort contains live yeast cells that are still actively converting sugars into alcohol and carbon dioxide. When added to the finished beer, these yeast cells continue to ferment, consuming any remaining fermentable sugars and producing carbon dioxide as a byproduct. This carbon dioxide is then trapped within the beer, resulting in natural carbonation.
Krausening is typically used on lager beers, which are brewed at lower temperatures and undergo a longer ageing process. During this cold and extended ageing period, the yeast used for fermentation can become dormant or settle to the bottom of the fermenter. By introducing fresh yeast through krausening, the beer is given a “second fermentation” and the yeast becomes active again, allowing for natural carbonation to occur.
One of the benefits of krausening is that it can help to create a finer and more persistent carbonation compared to forced carbonation methods. This natural carbonation process can result in a smoother and creamier mouthfeel, as well as a more balanced and integrated carbonation profile.
In my own experience as both a sommelier and brewer, I have found that krausened beers often exhibit a more lively and effervescent carbonation, with smaller bubbles that gently dance on the palate. This can enhance the overall drinking experience and contribute to a more refreshing and enjoyable beer.
It is important to note that krausening requires careful timing and monitoring to ensure that the beer is not overcarbonated or undercarbonated. The addition of too much actively fermenting wort can lead to excessive carbonation and potentially cause the bottles to explode. On the other hand, if too little wort is added, the beer may lack sufficient carbonation and appear flat.
Krausening is a traditional and labor-intensive method of naturally carbonating beers. While it may require more time and attention compared to other carbonation techniques, it can result in a unique and flavorful beer with a natural and lively carbonation.