Papaine is the common name for a proteolytic enzyme found in the seeds of the tropical fruit Papaya.It is used as a meat tenderizer (it means softens the fibers of the meat to make it more juicy and chewable),this is possible due to the activity of the enzime that breaks the chemical bonds in meat protein.
Several ways are available of tenderising meats, generally after culling the carcas should be left for 2 - 3 weeks to mature and let the natural fibres of the meat deteriorate slowly so they are not so closely bound. Once you have your steak there are several methods dependant upon whether you want to introduce new flavours to the meat or just want the natural taste or the steak. Long slow cooking is the key so the gentle heat breaks down the fibres, tenderising salts and commercially available tenderising mixes generall contain papaine which is derived from the papaya fruit, this acts as a natural tenderiser breaking down the enzymes in the meat, it is available nationally or you could even just marinate the meat with papaya slices. Another alternative is to give the meat a good bashing, several meat mallets are available, we found several at Kitchenaria www.kitchenaria.com they work by physically breaking down the meats fibre and muscle ensuring a tender steak without additional flavourings being incorporated into the final dish.
Meat tenderizers are proteolytic enzymes. These enzymes break the peptide bonds between proteins (amino acids) found in meat. Collagen is the complex protein that holds meat together. Some tenderizers are made of pineapple stem and papaya. These have natural proteollytic enzymes.