CROP CHEMISTRY 119 



or at least not enough to give good baking quality to bread 

 made from them. 



The straws from these grains are not as a class very 

 digestible, except possibly barley and oat>. The ash is high 

 in silica and potash. 



(b) Legumes. — These seeds are particularly high in protein 

 and correspondingly low in carbohydrates. The soja bean 

 contains considerable fat. 



(c) Miscellaneous. — Cotton Seed and Flax -Seed (Fig. 26) are 

 very high in fat and are used for the oil which can be expressed 

 from them (Section 69, c and d). The press cake is used as 

 a feeding stuff and fertilizer on account of its high nitrogen 

 content. These seeds are also high in fiber and very low 

 in carbohydrates. 



100. Fruit Crops (Fig. 27). — These crops are remarkable 

 for the extremely large amounts of water which they contain. 

 A pound of peach pulp or of strawberries, for example, 

 contains more water than a pint of milk. It is this 

 water content which makes fruit such a valuable addition 

 to the ordinary forms of food. The dry matter of fruits 



\s A. 



contain, in some cases about as much protein as the grains, 

 in most cases more crude fiber, in many cases more nitrogen- 

 free extract. When the fruit is green, the nitrogen-free 

 extract consists largely of starch, which is converted to such 

 soluble sugars as sucrose and dextrose during ripening. There 

 are also present in the nitrogen-free extract some acids or 

 acid salts. Certain volatile flavoring oils are included in the 

 crude fat. The ash of fruits is very largely basic in character 

 and this makes fruit verv valuable as a food. Potash is 

 an important constituent, being necessary for the ripening 

 process. 



101. Stem and Leaf Crops. — These crops when green are 

 high in water which is largely eliminated during the curing 

 process (Section 103). The dry matter of these crops is 

 high in ash and crude fiber, but low in nitrogen-free extract 

 and fat. They are not so high in crude fiber as the straws of 

 the grains, partly because they are cut before so much of 

 the starch and other digestible carbohydrates are changed to 

 crude fiber. The ash is rich in lime and potash, but not much 



