Isinglass place of Russian isinglass. The bladders, once removed from the fish, processed, and dried, are formed into various shapes for use. Before the inexpensive production of gelatin and other competing products, isinglass was used in confectionery and desserts such as fruit jelly and "blancmange". Isinglass finings are widely used as a processing aid in the British brewing industry to accelerate the fining, or clarification, of beer. It is used particularly in the production of cask-conditioned beers, although a few cask ales are available which are not fined using isinglass. The finings flocculate the live yeast in the beer into a
Swim bladder fins to produce lift while swimming. The gas/tissue interface at the swim bladder produces a strong reflection of sound, which is used in sonar equipment to find fish. Cartilaginous fish, such as sharks and rays, do not have swim bladders. Some of them can control their depth only by swimming (using dynamic lift); others store fats or oils with density less than that of seawater to produce a neutral or near neutral buoyancy, which does not change with depth. The swim bladder normally consists of two gas-filled sacs located in the dorsal portion of the fish, although in a few