This is another proteolytic enzyme found in the juices of pawpaw or papaya fruit, used as meat tenderizer under the trade name of Caroid. Papain increases its rate of reaction as the temperature raises to about 80 degrees Centigrade, (175 degrees Fahrenheit) and then it is rapidly deactivated. What this means is that papain continues its tenderizing role and at an increasing rate, during the earlier stages of cooking.
Similar to papain is ficin, enzymes found in figs. The uses of papain are similar to these of bromelain above.