FOODS AND DIET. 213 



II. Vegetables, especially potatoes. They contain starch and sugar. 



III. Fruits contain sugar, and organic acids, tartarie, malic, citric, 

 and others. 



C. Substances supplying fatty bodies principally. 



The chief are butter, lard (pig's fat), suet (beef and mutton fat). 



D. Substances supplying the salts of the food. 



Nearly all the foregoing substances in A, B, and C, contain a greater 

 or less amount of the salts required in food, but green vegetables 

 and fruits supply certain salts, without which the normal health of the 

 body cannot be maintained. 



E. Liquid foods. 



Water is consumed alone, or together with certain other substances 

 used to flavor it, e.g., tea, coffee, etc. Tea in moderation is a stimulant, 

 and contains an aromatic oil to which it owes its peculiar aroma, an as- 

 tringent of the nature of tannin, and an alkaloid, theine. The compo- 

 sition of coffee is very nearly similar to that of tea. Cocoa, in addition 

 to similar substances contained in tea and coffee, contains fat, albuminous 

 matter, and starch, and must be looked upon more as a food. 



Beer, in various forms, is an infusion of malt (barley which has 

 sprouted, and in which its starch is converted in great part into sugar), 

 boiled with hops and allowed to ferment. Beer contains from 1.2 to 8.8 

 per cent of alcohol. 



Cider and Perry, the fermented juice of the apple and pear. 



Wine, the fermented juice of the grape, contains from 6 or 7 (Rhine 

 wines, and white and red Bordeaux) to 24-25 (ports and sherries) per 

 cent of alcohol. 



Spirits, obtained from the distillation of fermented liquors. They 

 contain upwards of 40-70 per cent of absolute alcohol. 



Effects of cooking upon Food. 



In general terms this may be said to make food more easily digestible; 

 this usually implies two alterations food is made more agreeable to the 

 palate and also more pleasing to the eye. Cooking consists in exposing 

 the food to various degrees of heat, either to the direct heat of the fire, 

 as in roasting, or to the indirect heat of the fire, as in broiling, baking, 

 or frying, or to hot water, as in boiling or stewing. The effect of heat 

 upon (a) flesh is to coagulate the albumen and coloring matter, to solid- 

 ify fibrin, and to gelatinize tendons and fibrous connective tissue. Pre- 

 vious beating or bruising (as with steaks and chops), or keeping (as in 

 the case of game), renders the meat more tender. Prolonged exposure 



