1826.] on the Art of Baking Bread, S7I 



unco inbined acid contained originally in the treacle, has thereby 

 more leisure to penetrate into the system of the dough, and to 

 produce a more complete separation of its particles. And it 

 may be mentioned as a circumstance in support of this explana- 

 tion, that though the period of keeping requisite in the prepara- 

 tion of gingerbread-dougli is generally from five to ten days, it 

 is sometimes materially less, and that without the manufacturer's 

 being able to assign any cause for the variation. But this, of 

 course, might be readily accounted for on the supposition, that 

 treacle generally contains a variable quantity of uncombined 

 acid, and that this ingredient is the true agent in developing 

 carbonic acid gas within the dough, by its action upon the alka* 

 line carbonate. Upon the whole, therefore, it seems not impro- 

 bable, that the mutual action of the potashes and treacle, out of 

 which results the gasifying of gingerbread-dough, consists in the 

 treacle containing a little uncombined acid, which, uniting with 

 the potashes, sets carbonic acid gas at liberty, and thereby ren- 

 ders gingerbread light and elastic. 



In the course of performing these experiments, the details of 

 which have been subjoined in a note to p. 278, and the results of 

 which have led to the above conclusions, it was impossible not 

 to be impressed with a sense of the inconveniences that often 

 arise to the baker from the delay occurring in the process, and 

 of the injury which may not unfrequently accrue to the consumer, 

 from the deleterious nature of one of the ingredients which is 

 •essential in the present system. This is the carbonate of potash, 

 which it is always necessary to use in such a quantity as gives a 

 distinct disagreeable alkaline flavour to the bread, whenever 

 this is not disguised by mixture with some aromatic ingredient. 

 Nor can there be much doubt, that if gingerbread, as now made, 

 were eaten in any considerable quantity, it would prove injurious 

 to any dehcate constitution, in consequence merely of the large 

 amount which it contains of this alkaline substance ; and if 

 such a consequence as this may follow, even in the case of the 

 most carefully-baked gingerbread, it is plain that in the hands 

 of a careless or unskilful mechanic, the employment of such an 

 ingredient is extremely inconvenient. It appeared, therefore, 

 •to be a very desirable matter to procure some substitute, which, 

 while it formed an equally well-raised bread, might save the 

 delay of the baker, be less disagreeable to the palate, and quite 

 harmless to the constitution ; and, accordingly, it was not 

 without experiencing very considerable pleasure, that after 

 having made various trials, a mode of compounding and pre- 

 paring the dough was actually found out, which appears to unite 

 all these advantages. The substitute which proved the most 

 perfectly successful was a mixture of common carbonate of 

 magnesia and tartaric acid ; and in mixing up the dough, there 

 iwill be found a practical expediency in employing a Qonsiderably 



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