Proteins are the most important elements in our daily diet. That is why; these are called the FIRST FOODS. There are proteins in both animals and vegetables; and no one can support life without protein in some form. This is because proteins alone contain sufficient amounts of the great element called Nitrogen, which forms a large part of every portion of our bodies. This is why they are called proteins, meaning “first foods,” or most necessary foods. Whatever we may live on in later life, we all began on a diet of liquid meat or liquid protein (milk), and could have survived and grown up on nothing else.
Composition of Proteins: Nearly all our meats are the muscle of different sorts of animals, made of a soft, reddish, animal pulp called MYOSIN; the other principal proteins being white of egg, curd of milk, and a gummy, whitish-gray substance called gluten, found in wheat flour. This gluten is the stuff that makes the paste and dough of wheat flour sticky, so that you can paste things together with it; while that made from corn meal or oatmeal will fall to pieces when you take it up. The jelly-like or pulp-like Myosin in meat is held together by strings or threads of tough, fibrous stuff; and the more there is of this fibrous material in a particular piece or “cut,” of meat, the tougher and less juicy it is. The thick, soft muscles, which lie close under the backbone in the small of the back, in all animals, have less of this tough and indigestible fibrous stuff in them, and cuts across them give us the well-known porter-house, sirloin, or tenderloin steaks, and the best and tenderest mutton and pork chops.