CHAPTER XVII 



CONCENTRATED FOODS 



UNDER the head of concentrated foods are included all those 

 products which contain relatively small proportions of water 

 and fibre, and which are, therefore, rich in nutrient material. 

 It was previously shown (p. 231) that they contain more than 

 12 per cent, of protein, or more than 50 per cent, of non- 

 nitrogenous matter reckoned as starch. 



With few exceptions they consist of seeds, portions of 

 seeds, or substances derived from them. For convenience 

 of study they may be classified as seeds, cakes, meals, 

 and industrial by-products. This classification, however, is 

 purely arbitrary. The by-products consist chiefly of the 

 residues obtained in brewing and distilling, and in the 

 manufacture of starch and sugar. The more important 

 meals are offals or by-products from the flour mills, and in 

 a sense oil-cakes might be regarded as by-products from the 

 oil mills. 



Seeds. All seeds consist essentially of two parts a 

 germ or embryo, and a store of nutrient matter to nourish 

 it during the process of germination and until the seedling 

 has reached a stage in which it is capable of independent 

 existence. The embryo consists mainly of protein and fat. 

 The nutrient matter consists partly of nitrogenous matter 

 and partly of non-nitrogenous. The former, in properly 

 ripened seed, is almost entirely true protein ; amides are 

 absent, or present only in very small proportion. The latter 

 usually consists mainly either of starch, or oil, or of both in 

 varying proportions. The ash is composed mainly of phos- 

 phates of potash, magnesium, and calcium. In the seed 



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