1826.] on the Art of Baking Bread, $f^ 



It was scarcely to be doubted that the action of the treacle 

 upon the carbonate consists in evolving from it a quantity of 

 carbonic acid gas. But in order to bring out this point more 

 unequivocally, the substitution of carbonate of soda and of 

 carbonate of magnesia for carbonate of potash, was tried, and it 

 invariably turned out that the bread in these cases expanded 

 just as well in the oven, as when an equivalent quantity of car^ 

 bonate of potash had been employed. And when, on the 

 contrary, in place of these substances, there was mixed up with 

 the dough either caustic potash or caustic magnesia, the bread 

 never expanded in the slightest degree in the process of baking, 

 whether the dough was baked when recent, or after being kept 

 a considerable time. From this it resulted, that the presence 

 of an alkaline carbonate was clearly essential to the gasifying 

 of the gingerbread-dough ; and it seemed almost a necessary 

 inference, that the rising of the bread during the baking is pro- 

 duced by carbonic acid gas, and that this gas is developed in 

 consequence of some mutual action which takes place between 

 the treacle and the alkaline carbonate.''^ 



* The following is a note in detail of the variously-compounded doughs employed 

 in these experiments, with a statement of the general results obtained. 



1. — Flour 4 ounces. 



Treacle 3 ounces. 



Potashes , 60 grains. 



Rose well in the baking : not distinguishable in appearance from that made with 

 ordinary gingerbread-dough. 



2.— Flour bounces. 



Treacle 3 ounces. 



Flour 4 ounces. 



Treacle 3 ounces. 



Butter. ^ ounce. 



The bread was quite compact, hard, and might even be termed flinty, 



3. — Flour 4 ounces. 



Potashes 60 grains. 



Flour ...» 4 ounces. 



Butter I; ounce. 



Potashes 60 giains. 



Flour 4 ounces. 



Refined sugar 3 ounces. 



Potashes 60 grains. 



Flour 4 ounces. 



Refined sugar 3 ounces. 



Butter I ounce. 



Potashes 60 grains. 



These four mixtures were made into dough with the requisite quantity of hot water ; 

 and portions of each mass of dough were baked in an oven, both immediately after its 

 preparation, and at an interval of five days subsequently. In both instances, the results 

 of all the four trials proved uniformly the same, and all alike unfavourable. The bread 

 never exhibited the slightest indications of expansion, being quite compact and sad. It 



New Series, vol, xii. t ' ^ 



