XIV. METHODS FOR THE ANALYSIS OF BEER. PROVISIONAL. 



1. Preparation of Sample. 



Transfer the contents of the bottle or bottles to a large flask and shake 

 vigorously to hasten the escape of carbon dioxid, care being taken that the 

 beer is not below 15 C., since below this temperature the carbon dioxid is 

 retained in the beer and is liable to form bubbles in the pycnometer. 



2. Specific Gravity. 

 Determine specific gravity as directed under " XIII. Wine," on page 83. 



3. Alcohol. 



(a) DISTILLATION METHOD. 

 Determine as directed under " XIII. Wine," on page 83. 



(b) OPTIONAL METHOD. 



Calculate the alcohol content from the reading of the Zeiss immersion refrac- 

 tometer on the distillate, reporting the results at 20 C. 



4. Extract, 

 (a) METHOD I. 



Evaporate 25 cc of the beer in a tared platinum dish to constant weight in a 

 water oven at 80 C. 



(b) OPTIONAL METHOD II. 



Calculate according to formula sp=0+(l a), in which sp is the specific 

 gravity of the dealcoholized beer, g the specific gravity of the beer, a the specific 

 gravity of the distillate obtained in the determination of alcohol, and deter- 

 mine value of sp from standard tables on extract in beer wort. (Tables III ami 

 IV. pp. 209 and 214.) 



(c) OPTIONAL METHOD III. 



Make immersion refractometer reading of dealcoholized beer and calculate 

 extract in grams per 100 cc. 



5. Extract and Specific Gravity of Original Wort. 



Calculate percentage of extract from the formula O=2A + E, when O=oriir- 

 inal extract of wort, A=alcohol by weight, and E=extract of dealcoholi/nl 

 beer. From extract calculated as above compute from standard tables tin* 

 specific gravity of the wort (See Tables III and IV. pp. 209 and 214.) 

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