14 BULLETIN 493, U. S. DEPARTMENT OF AGRICULTURE. 
tive material from 68 pounds of malt and 23 pounds of cerealin, while 
in the first product there is present the extractive material from only 
58 pounds of malt. Since the analysis is made upon the finished 
liquid it is evident that the percentage composition of any particular 
ingredient should be very much larger in the second product "because 
of the very much larger amount of material used in its preparation. 
It is apparent, therefore, that no direct comparison can be made 
between the percentage composition of these different brews in order 
to determine the effects of the raw materials upon their composition. 
The most satisfactory way to have tested this question of the effect 
of raw materials on the finished product would have been to make a 
series of worts with exactly the same percentage of solids, some of 
pure malt and others of mixtures of pure malt and corn, rice, and 
cerealin; then a direct comparison between the results would have 
shown the effects of these various materials. ~This method was 
impracticable because it was necessary to take the brews as actu- 
ally made under varying commercial conditions. The object sought 
can be accomplished, however, by calculating the results of these 
analyses either to the basis of dry material in the original wort or by 
calculating them to the basis of a wort with constant water content. 
It was decided to calculate all of the results to the basis of a wort 
containing 15 per cent of solids, as this would give a uniform basis 
for comparison and would be approximately an average wort. The 
method employed in calculating the various beers and ales to this 
uniform basis was as follows: 
The percentage of solids in the original wort was calculated by 
multiplying the percentage by weight of alcohol by 2 and adding the 
percentage by weight of extract. The result for an ordinary beer 
would be about 12 per cent, while in the case of a very heavy ale it 
might be as high as 18 or 20 per cent. The actual percentages of 
protein, ash, and phosphoric acid found by analysis were then cal- 
culated to the basis of a uniform wort containing 15 per cent of solids. 
This was the method used for preparing the second part of this table. 
A study of this portion of the table shows the actual effects of the 
various substitutes used for malt on the composition of the fermented 
product. For instance, the first of the all-malt beers from brewery 
No. 2 (22017-D) showed in the analysis of the original product a pro- 
tein percentage of 0.603, an ash percentage of 0.206, and a phosphoric 
acid percentage of 0.079. When calculated to the basis of a wort 
containing 15 per cent of solids instead of 12.72 per cent (the actual 
percentage of solids in the wort from which it was made), it gave the 
following percentages: Protein, 0.712; ash, 0.243; and phosphoric 
acid, 0.093. In the case of brewery No. 3, sample No. 29512-B, 
where the original analysis of the product showed 0.650 per cent of 
protein, 0.266 of ash, and 0.057 of phosphoric acid, it will be found 
that when this product is calculated to the basis of a wort of 15 per 
