MAKING BREAD. 149 



fall to the bottom of the vessel where it is collected; 

 the siiffar will be held in solution in the water em- 

 ployed, and the gluten will remain alone. 



There are three sorts of bread in general use, 

 prepared from wheat flour : 1. Unleavened 

 bread. 2. Leavened bread. S. Bread made with 

 yeast. 



Unleavened Bread. 



When flour is kneaded with water, it forms a 

 tough adhesive paste, containing the constituent 

 principles of flour, with little or no alteration, and 

 not easily digested by the stomach. 



When formed into cakes, and baked by heat, the 

 gluten, and probably the starch, undergo a con- 

 siderable change, and the compound is rendered 

 more easy of digestion. 



Bread made in this manner, without any addition, 

 is called unleavened bread. It is not porous, but 

 solid and heavy. 



This is, no doubt, the most ancient method of 

 preparing bread, and it is still used in many coun- 

 tries. The oat cakes, and barley bread, used in 

 Scotland, and the north of England, are of this 

 kind ; so are also biscuits of all kinds. 



Unleavened bread is also used by the Jews 

 during the Passover. 



OfLeave7ied Bread. 



When flour is kneaded with water, it is called 

 dough ; and when this is kept in a warm place, it 

 swells up, becomes spongy, and is filled with air- 

 bubbles ; it disengages at length an acidulous and 

 spiritous smell, tastes sour, and in this st3>t,e is called 

 leaven, .7.: . 



Here the saccharine part has been converted 

 into ardent spirit, the mucilage tends to acidity, 



L 3 



