CHAPTER XI. 



FOOD INGREDIENTS. CHEMICAL TERMS EXPLAINED. 



WATER. If a piece of wood or wisp of hay be dried some time in 

 a hot oven, more or less water will be driven off. The water in feeding- 

 stuffs varies from So to 90 pounds in every 100 pounds of young grass 

 or foddcr-com, to only 8 or 10 pounds to the 100 in dry straw or hay. 



ORGANIC SUBSTANCE. If the dried wood or hay be burned, most of 

 it will pass oil as gas, vapor, or smoke. The part thus burned away is 

 the organic substance. The residue : 



THE ASH contains the mineral matters, that is, the potash, lime, phos- 

 phoric acid, <Scc., of the plant. The most important part for our present 

 purpose is the organic, the combustible matter. This consists of three 

 kinds of ingredients, albuminoids, carbo-hydrates, and fats. The main 

 point in economical feeding is to secure the right proportions of these 

 at the lowest cost. 



ALBUMINOIDS also called protein compounds, proteids, and flesh- 

 formers contain carbon, oxygen, hydrogen and nitrogen. Thus they 

 differ from the carbo-hydrates and fats, which contain no nitrogen. 

 The name albuminoids comes from albumen, which we know very well 

 as the whites of eggs, and it is found in milk. The fibrin of bone and 

 muscle (lean meat) and the casein (curd) of milk are also albuminoids. 

 Indeed, the solid part of blood, nerves, lean meat, gristle, skin, &c., con- 

 sist chiefly of albuminoids. In plants they are equally important ; plant 

 albumen occurs in nearly all vegetable juices, especially in potatoes and 

 wheat, casein or legumin in beans and peas, and fibrin in the gluten of 

 wheat, the basis of what farmer-boys call " wheat gum." Clover, bran, 

 beans, peas, oil-cake, and flesh and meat-scrap are rich in albuminoids. 



CARBO-HYDRATES consist of carbon and hydrogen. The most impor- 

 tant arc starch, sugar, and cellulose (woody fibre) . They make up a 



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