Vani Hari ingredient. NPR cited this as an example of fearmongering and lack of subject matter knowledge, as isinglass, derived from fish swim bladders, has been used as a natural fining agent in food and drink for centuries, and is in any case used primarily in cask ale, not vat-brewed beers, which are normally cleared by filtering. The day after she posted her petition, Anheuser-Busch and MillerCoors released ingredients in many of their products. The trade publication "Beer Marketer's Insights" called Hari's petition an "attempt of fear mongering in the name of advocacy." Hari later claimed that she was aware of the
Swim bladder duct, allowing the fish to fill up the swim bladder by "gulping" air. Excess gas can be removed in a similar manner. In more derived varieties of fish (the physoclisti) the connection to the digestive tract is lost. In early life stages, these fish must rise to the surface to fill up their swim bladders; in later stages, the pneumatic duct disappears, and the gas gland has to introduce gas (usually oxygen) to the bladder to increase its volume and thus increase buoyancy. In order to introduce gas into the bladder, the gas gland excretes lactic acid and produces carbon