1 6 APPLIED PHYSIOLOGY 



cooked if it is to be of any use to his body. Cooking 

 does not change sugar. 



Cooking simply melts fat, but does not change it, unless 

 the heat is great enough to burn it. But in meat and 

 vegetables, cooking softens the pockets of albumin in which 

 the fat is stored, and sets it free, so that it floats upon the 

 water. In this way pure lard and tallow are made. 



Cooking develops the taste of food so that it is more 

 agreeable to the body. It also destroys many poisons in 

 food. 



16. Ways of cooking. Man applies heat in cooking in 

 three ways. He boils the food in water, or surrounds it 

 with heat in a hot oven, or exposes one side at once to the 

 heat, as in broiling. It makes little difference how it is 

 done, so long as it is done well. Cooked food should taste 

 good and be either soft, or else brittle, so that it can be 

 chewed fine. If food is tough or doughy, so that it cannot 

 be chewed well, it is surely not well cooked. 



After the food is cooked we put it upon a plate and cut 

 it into fine bits. This saves the mouth a great deal of 

 work and keeps us from eating too fast. Every one should 

 take time to cut his food into small pieces before eating it. 



17. Mouth digestion. After the food is cooked, man 

 takes it into his mouth, and there continues its digestion 

 by grinding it between his teeth and rolling it about with 

 his tongue and cheeks, until it is in fine particles. At the 

 same time he mixes it with a watery fluid so that it is like 

 a thin paste. 



18. The teeth. The teeth are bony pegs set into the 

 jaw bones. Those in the front part of each bone are 

 sharp in order to bite off lumps of food. Those in the 

 back part of the mouth are flat so as to grind the food to 

 pieces. Between the ages of six and thirteen years a 



