From the testing on cleaning the pig’s stomach, the pig’s stomach that is cleaned by using cleaning method A (which using salt, corn flour and papaya leaf to clean the pig’s stomach) is clean, tender and not smelly. For the pig’s stomach that is cleaned by using cleaning method B (which using only salt and corn flour to clean the pig’s stomach) is clean, tough and smelly. While, for the pig’s stomach that is cleaned by using cleaning method C (which using salt, corn flour and coca-cola to clean the pig’s stomach) is clean, tender and not smelly.
The pig’s stomach is high in protein and low fat. The inner of pig’s stomach contains a yellow layer of mucous membrane (stomach juice, fat and etc). This layer of mucous membrane is removed by rubbing the pig’s stomach with salt and corn flour. The pig’s stomach is tough because it is very muscular. The muscles of pig’s stomach are made of strong fibers. The fibrils, which have a complex internal structure bound together by long protein chains, give the muscles their structural integrity so that the muscles can contract. Besides that, the pig’s stomach is tough because of the connective tissue, which is mostly protein, holds the muscles of pig’s stomach together. Hence, the pig’s stomach that is cleaned by using only salt and corn flour is clean, tough and smelly. (http://books.google.com.my/
In general, enzyme is the complex molecule that produced in living organisms and functions as chemical reaction catalyst within the cell. The papaya leaf is rich of latex that contains a protein-cleaving enzyme, which is known as papain. Besides that, papain is also called proteolytic enzyme or protease, which is the enzyme that breaks down the protein into smallest element. Therefore, papain has the ability to act as pig’s stomach tenderizer because the pig’s stomach is high in protein. The structural integrity of the muscle fibers in pig’s stomach is disrupted due to the papain cuts the protein chains in fibrils and connective tissue, and thus, the pig’s stomach become tender. In additions, the papaya leaf is also able to break down the carbohydrate and fat due to the presence of papain. Hence, the pig’s stomach is not smelly (pig’s smell) due to the carbohydrate (food that retained in the pig’s stomach) and fat (fat layer in the inner of pig’s stomach) are broken down. Based on those factors, the pig’s stomach that is cleaned by using salt, corn flour and papaya leaf is clean, tender and not smelly. (http://www.herbalist.com/
Besides papaya leaf, there has another method that also can make the pig’s stomach become clean, tender and not smelly. The method used is clean the pig’s stomach by using salt, corn flour and coca-cola (http://www.angelofoz.com/