239 



The consumption of baking powders in the United States is given 

 as nearly as it could be ascertained in the absence of an}^ established 

 statistics on this point. Baking powders are classified in three prin- 

 cipal divisions, according to the nature of the acid constituent used 

 in driving off the carbonic-acid gas. Each of these classes is taken 

 up in turn, the chemical reactions whicli occur when the powder is 

 dissolved are stated, and the nature of the residue is discussed. 



Particular attention is paid to the class of baking powders known 

 as alimi powders, on account of the prominence which Jias been given 

 10 the question of the henlthfulness and propriety of the use of alum 

 in breadstuff's. Various opinions and authorities are quoted on both 

 sides of the question and conclusions are drawn in so far as the evi- 

 dence will permit. The different classes of baking powders are also 

 comi)ared with reference to their relative aerating strength and the 

 amount of residue left by each. 



The composition of baking powders as found in the market is next 

 considered. Full abstracts are made of official reports upon this sub- 

 ject by Prof. PI. A. AVeber, in the " First Annual Report of th? Ohio 

 State Dairy nnd Food Commission for 1887," which gives the results 

 of a partial analysis of a large number of samples; and by Professor 

 Cornwall, in the " Report of the Dairy Commissioner of New Jersey 

 for 1888." The analyses made in the course of the investigation by 

 this Department are also given, and the methods of analysis U'-ed are 

 discussed in detail, together with the comparative results of different 

 luethods. The methods of analysis used include the following deter- 

 minations: Estimation of carbonic acid, both total and available; 

 estimation of starch by direct determination; estimation of phos- 

 phoric acid, of tartaric acid, alkalies, aluminum, calcium, sulphuric 

 acid, ammonia, and moisture. The results of the analyses are given 

 in full, the percentage composition being calculated in one table and 

 the probable percentage combination in another, with notes and com- 

 ments upon peculiar combinations and constituents in certain cases. 

 Hie results of the analyses were found to agree substantially with 

 those obtained in the investigations of Professors AVeber and Corn- 

 wall. 



The difficulties in the way of the preparation of baking powders in 

 the household are stated, and simple formulas are given whereby, 

 with proper care, any housekeeper may make up baking powder 

 Avhich will be in all respects equal if not superior to any of the 

 brands sold in the market and much less expensive. 



Tlie regulation of the sale of baking powders by law is advocated 

 in so far as to require ihe formula and composition of each brand 

 to be printed on the package, in order that the consumer may be fully 

 informed of the character of the jiowder which he buys. 



