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 the blood reaches the heart. Primitive lungs gave an advantage by supplying the heart with oxygenated blood via the cardiac shunt. This theory is robustly supported by the fossil record, the ecology of extant air-breathing fishes, and the physiology of extant fishes. In embryonal development, both lung and swim bladder originate as an outpocketing from the gut; in the case of swim bladders, this connection to the gut continues to exist as the pneumatic duct in the more "primitive" ray-finned fish, and is lost in some of the more derived teleost orders. There are no animals which have both lungs