Dr Colquhoun on the Art of baking Bread. 83 



taonic acid gas, was found to impart to the simple bread a 

 slightly vapid taste ; but the addition of a very trifling quantity 

 of sugar is quite sufficient to conceal this. There is subjoined 

 in a note, the process followed in preparing biscuit with these 

 ingredients, which is indeed so simple, as scarcely to require 

 any particular explanation. 



" Such is the mode of preparing a well-raised gingerbread, 

 which, out of a variety of trials, seemed by far the most success- 

 ful, and the most advantageous, both to the manufacturer and 

 to the consumer. But there are various other ingredients 

 which may be effectually enough employed for the same end, 

 and some of which deserve to be mentioned, as tending to throw 

 light upon the rationale of the process, which is, in principle, 

 the same in every case. 



" Thus, for example, the bitartrate of potash, instead of tar- 

 taric acid, may be employed, along with the carbonate of mag- 

 nesia. When this substance is used, there is a degree of sour- 

 ness, just perceptible to the palate, in the flavour of the bread, 

 and which it is not impossible that some tastes might regard 

 in the light of an improvement. Another method, and quite 

 an effectual one, is to use the carbonate of magnesia alone, with- 

 out any acid admixture, only to an extent doubly or trebly 

 greater than when it is conjoined with tartaric acid ; and the 

 result will be that the dough becomes as speedily fit for being 

 baked, and yields as spongy and as light a bread. If again the 

 carbonate of potash, along with an equivalent quantity of sul- 

 phuric acid, be intermixed with dough, it has the effect of fit- 

 ting it for the oven as speedily as any of the other methods 

 above-mentioned. But it communicates to the bread a taste 

 decidedly bitter. 



" There have now been detailed a few of the modes, in which 

 much delay and trouble may be saved to the manufacturer by 

 his employing the mutual action of an acid and of an alkaline 

 carbonate, which shall take a speedy effect, and generate a due 

 supply of carbonic acid gas within the dough, after it is made. 

 It is only, however, the first mentioned substitute for the pre- 

 sent noxious ingredients of carbonate of potash and alum which 

 can be considered the best adapted for practice, both as being 

 in itself the most convenient and simple, and also as possessing 



