150 MAKING BREAD. 



and the gluten probably verges towards a state of 

 putridity. By this incessant fermentation, the 

 mass is rendered more digestible and light, that 

 is, it becomes much more porous by the disengage- 

 ment of elastic fluid, which separates its parts from 

 each other, and much enlarges its bulk. The 

 operation of baking puts a stop to this process, by 

 evaporating a great part of the moisture, which 

 favours the chemical attractions, and probably also 

 by further changing the nature of the component 

 parts. Bread, however, in this state, will not pos- 

 sess the requisite uniformity. In order to promote 

 an uniform fermentation, a small portion of Jeaven 

 is intimately blended with a quantity of other 

 dough, which, by the aid of heat, diffuses itselfj 

 and causes all the parts to ferment at the same 

 time, As soon as the dough has acquired a suffi- 

 cient bulk from the extrication of carbonic acid 

 gas, it is considered as fit for the oven. It will be 

 necessary here to consider more at large the nature 

 of the fermentation, which is so essential in the 

 making of good bread. 



When wheat-flour and water are mixed, the 

 saccharine extract of the flour, in consequence of 

 heat and moisture, has its constituent principles 

 disunited ; the oxygen seizes the carbon, forming 

 carbonic acid, which flies off in the form of gas, 

 and occasions that internal motion and increase 

 which appears. This process, if left to itself, is 

 extremely slow, and is therefore accelerated by the 

 addition of more dough and warm water. The 

 gluten, being dispersed through every part of the 

 mass, forms a membrane among the dough, which 

 suffers the carbonic acid gas to* expand, but pre- 

 vents its total escape, thus causing that porous 

 reticulated appearance, which fermented bread 



