94 VEGETABLES. 



The gluten is the most nourishing part of wheat ; and 

 that wheat is best which contains most of it. 



170. Caseine^ which strongly resembles curd, is 

 found abundantly in peas and beans. It is soluble in 

 water, and will coagulate, like the curd in milk, if an 

 acid, as vinegar or rennet, be added. 



171. Albumen abounds in oily seeds, as poppy 

 seed, flax-seed, &c. It is soluble in water, but coagu- 

 lates, like the white of eggs, if boiled. 



172. You can easily separate the constituents of 

 flour, and examine them in the following manner : 



173. Wash two or three ounces of fine flour on a 

 piece of linen or cotton cloth of medium thickness, 

 with as many pints of water. Pour on fhe water, a 

 little at a time, and stir the flour gently on the cloth, 

 letting the water fall into a pan below. What re- 

 mains on the cloth is gluten. After the water has 

 stood in the pan long enough to become perfectly 

 clear, pourdt into a k-ettle so gently as not to disturb 

 the sediment. What remains in the pan is starch. 

 Then heat the kettle till the water boils, and the albu- 

 men will be seen in a coagulated state, having some 

 resemblance to the white of an egg after being par- 

 tially boiled. 



174. I have already stated that gluten, albumen, 

 and caseine are nitrogenous substances, and that they 



