BREAD. 229 



water thus added to flour enters into intimate combination 

 with its constituents, and but little of it is expelled by the heat 

 to which it is exposed in baking. Bread that has been removed 

 from the oven several hours, has been found to contain about 

 forty-five per cent, of water, and the proportion is but slightly 

 lessened by age. As what we call dry flour contains about 

 twelve per cent, of water, there will therefore remain of the 

 water that was added in the preparation of the dough, about 

 thirty-five per cent., or a little more than one-third of the whole 

 weight of bread. The water thus intermingled with the flour 

 combines with the starch, dissolves the sugar and gluten, and 

 moistens the minute particles so as to cause them to cement 

 together, binding the whole into a coherent mass. It also serves 

 to bring the ingredients into that closer contact which is favor- 

 able to chemical activity. The proper quantity of water to be 

 used is so much as will give to the gluten the greatest degree 

 of tenacity ; experience shows this to be about a half pint to a 

 pound of flour. 



A mixture of plain flour and water makes a substance which, 

 when baked, is hard and tough, and difficult to masticate and 

 digest. To remedy this defect, and give the bread a loose and 

 spongy texture, which enables it better to mingle with the 

 digestive juices of the stomach, the dough is subjected to 

 certain operations which we call raising. When softened by 

 water, the glutinous parts of the flour become elastic, and thus 

 the whole mass is rendered capable of greatly expanding. To 

 produce this desirable expansion, fermentation is usually em- 

 ployed. While the vinous fermentation is going on, the sugar 

 of the flour is changed to alcohol and carbonic acid gas. The 

 particles of sugar being evenly distributed through the mass, 

 wherever the fermentation is sufficiently active, the liberated gas 

 forms little cells for itself in the elastic dough ; and the gas bub- 

 bles, being confined by the toughness of the gluten in the spot 

 where they are generated, expand or raise the whole lump, 

 giving it the requisite lightness. All rising of bread depends 

 upon this principle — there must be minute bubbles of gas liber- 

 ated evenly in all parts of the dough. In all modes of ferment- 

 ation, in all combinations of alkali and acid, the result is 

 effected in the same way. 



