Sitat wiki:
Isinglass finings are widely used as a processing aid in the British brewing industry to accelerate the fining, or clarification, of beer. They are used particularly in the production of cask-conditioned beers, known as real ale, although there are a few cask ales available which are not fined using isinglass. The finings flocculate the live yeast in the beer into a jelly-like mass, which settles to the bottom of the cask. Left to itself, beer will clear naturally; however, the use of isinglass finings accelerates the process. Isinglass is sometimes used with an auxiliary fining, which further accelerates the process of sedimentation.
Non-cask beers which are destined for kegs, cans or bottles are often pasteurized and filtered. The yeast in these beers tends to settle to the base of the storage tank naturally, so the sediment from these beers can often be filtered without using isinglass.[citation needed] However, some breweries still use isinglass finings for non-cask beers, especially when attempting to repair bad batches.
Altså er det i hovedsak brukt ved naturlig karbonering. Dette var meget overraskende. Det vil si at jeg absolutt ikke har bruk for dette middelet da mitt øl vanligvis klarner iløpet av en uke eller to