A STUDY OF AMERICAN" BEEES AND ALES. 3 
METHODS OF ANALYSIS. 
The methods of analysis used were those given in Bulletin 107, 
revised (U. S. Dept. Agr., Bur. Chem.), pages 90-94, with the exception 
that the determination of phosphoric acid was made by the method 
used in fertilizer analysis (ibid., pp. 2-5), destroying the organic 
material in the beer by digestion with strong sulphuric acid and 
nitric acid and determining the phosphoric acid finally by the op- 
tional volumetric method (ibid., p. 4). The uranium acetate method 
given for beers was not used, for the reason that it was found to be 
exceedingly difficult to obtain accurate results on dark-colored beers. 1 
It was found in the estimation of dextrin by the Sachsse-AUihn 
method (ibid., p. 91) that there is an error in the method of cal- 
culation of the amount of dextrose formed from the amount of 
maltose in the original beer. Instead of multiplying the amount 
of maltose in the original beer by the factor 0.9, it should be multi- 
plied by the factor 1.053, as 1 gram of anhydrous maltose yields, on 
hydrolysis, 1.053 grams of dextrose. The product is the quantity 
which should be subtracted from the total amount of dextrose found 
after hydrolysis. The extract in the beer was determined by use of 
the tables of Schultz and Ostermann (ibid., pp. 209-213). The same 
methods were used in the analyses of the worts as were used in the 
examination of the beers. 
RESULTS OF ANALYSIS. 
Tables I to IV contain the results of the analyses of the worts and 
finished fermented products obtained at the various breweries where 
this investigation was conducted, arranged so as to show readily the 
changes which took place during fermentation and, in a few cases, 
the changes which took place during storage. The results are all 
given in terms of grams per 100 cc, so that a direct comparison of 
the quantities of any particular ingredient in a definite volume of 
material may be made. The comparison of the grams per 100 cc 
of an ingredient in the wort, with the grams per 100 cc in the finished 
fermented product, is based on the assumption that there is no appre- 
ciable change in the volume of the wort during fermentation. 
In Table I are given the results of the analyses of 7 malt worts and 
the beers produced from them. Table II contains the results of the 
analyses of 2 malt-and-rice worts and 2 malt-and-corn worts, and 
1 Riley, in his report to the Association of Official Agricultural Chemists for the year 1913, stated that 
the method giving the most uniform results was that of ashing the beer with an excess of standard calcium 
acetate, and that while the moist combustion method in the hands of those familiar with it gave satisfac- 
tory results, the various collaborators working with the method did not get as uniform results as with the 
method of ashing with calcium acetate. J. Assoc. Off. Agr. Chemists 1 (1915), 138-143. 
