10 COMMERCIAL FKEDING STUFFS. 



manufacturing processes, that the various mixtures may be classified 

 and some idea gained of what their composition should be. 



COTTONSEED MEAL. 



Cottonseed meal is a by-product. from the manufacture of cotton- 

 seed oil. The seeds as they come from the ginning mill are cov- 

 ered with a hard shell and a coating of lint. At the oil mills the 

 fuzzy seeds are subjected to a rough milling for the removal of the 

 black hull and lint. The decorticated seeds are crushed, heated, 

 placed in jute sacks, and subjected to hydraulic pressure, by means 

 of which a portion of the oil is expressed. When the resulting cake 

 is cracked and ground the yellow cottonseed meal of commerce 

 is obtained. 



LINSEED MEAL. 



At the oil mills the seeds are crushed and then the oil is removed 

 by one of two processes. 



In the "old process," the crushed seeds are heated, placed in jute 

 sacks, and subjected to hydraulic pressure. The residue consists of 

 hard slabs or cakes, which are cracked and ground, the product being 

 known as "old process" oil meal. 



In the ''new process," the crushed seeds are heated and while 

 warm are placed in large vertical percolators, and naphtha or some 

 other volatile solvent is poured over them, which is allowed to drain 

 out at the bottom. This process is repeated until nearly all the oil 

 has been removed. The extracted mass is freed from solvent by letting 

 steam into the percolator and driving out the naphtha as a vapor. 



After steaming, the meal is dried, and the resultant by-product is 

 known as "new process" oil meal. 



GLUTEN, GLUTEN MEAL, GLUTEN FEED. 



These materials are usually obtained as by-products in the manu- 

 facture of starch and glucose from corn. The method is practically 

 as follows: The whole corn is soaked for several hours in warm acidi- 

 fied water until soft and swollen. It is then ground in running water 

 and passed through sieves, the starch and part of the gluten passing 

 through, while the husk and germ remain behind. The starch and 

 gluten which are carried by the water are separated from each other 

 by their difference in specific gravity. The by-products are first dried 

 by pressure and then in a kiln. The gluten when sold alone is gem-r- 

 ally called ''gluten meal." More frequently, however, the gin ten, 

 husk, and germ are mixed and sold under the name of "gluten feed." 



