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 dioxide. The resulting acidity causes the hemoglobin of the blood to lose its oxygen (Root effect) which then diffuses partly into the swim bladder. The blood flowing back to the body first enters a rete mirabile where virtually all the excess carbon dioxide and oxygen produced in the gas gland diffuses back to the arteries supplying the gas gland. Thus a very high gas pressure of oxygen can be obtained, which can even account for the presence of gas in the swim bladders of deep sea fish like the eel, requiring a pressure of hundreds of bars. Elsewhere, at a