Papain is a protease present in papaya which is useful in tenderizing meat and other proteins. Its utility is in breaking down the tough meat fibers and has been utilized for thousands of years in its native South America. It is sold as a component in powdered meat tenderizer available in most supermarkets. It is also sold as a dietary supplement to remedy indigestion.

GoldBamboo

... Enzymes accelerate reactions within body cells. In the human body, the pancreas usually produces enzymes that break down foods into nutrients that the body can use for energy and other functions. Enzyme deficiencies are rare, but individuals who have cystic fibrosis or diseases of the pancreas may not produce enough natural enzymes to digest foods properly. Papain, an enzyme produced by the tropical fruit, papaya, is proteolytic, which means that it digests proteins. Frequently, papain is included in prescription combinations of digestive enzymes to replace what individuals with cystic fibrosis or pancreas conditions cannot produce naturally. Because it improves digestion in general, papain has also been used orally to treat less serious digestion disorders such as bloating and chronic indigestion. Since parasitic organisms are largely proteins, papain has sometimes been taken internally to eliminate intestinal worms, but this use is rare today. ...
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?Papaya Papaya trunk with immature fruit Scientific classification ...
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