XVI. WINES. 



1 PHYSICAL EXAMINATION.-TENTATIVE. 



Note the following: whether the container is "bottle full"; the appearance of 

 the wine, whether there is any sediment and if it is bright or turbid; condition when 

 opened, whether still, gaseous or carbonated; color and depth of color; odor, whether 

 vinous, acetous, pleasant or foreign; and taste, whether vinous, acetous, sweet, 

 dry or foreign. 



2 PREPARATION OF SAMPLE.— TENTATIVE. 



If gas is contained in the wine, remove it by pouring back and forth in beakers. 



Filter the wine, regardless of appearance, before analysis and determine immedi- 

 ately the specific gravity and such ingredients as alcohol, acids and sugars as are 

 liable to change through exposure. 



3 SPECIFIC GRAVITY.-TENTATIVE. 



Determine the specific gravity at -^s—^ by means of a pycnometer. 



4 ALCOHOL.— TENTATIVE. 



(a) By volume.— Measure 100 cc. of the liquid at 20°C. into a 300-500 cc. distilla- 

 tion flask, add 50 cc. of water, attach the flask to a vertical condenser by means of 

 a bent tube and distil almost 100 cc, making up to 100 cc. volume when cooled 

 to 20°C. Foaming, which sometimes occurs, especially with young wines, may be 

 prevented by the addition of a small amount of tannin. To determine the alcohol in 



wines which have undergone acetous fermentation and contain an abnormal amount 

 of acetic acid, exactly neutralize the portion taken with sodium hydro.xid solution 

 before distilling. This is unnecessary, however, in wines of normal taste and odor. 

 Determine the specific gravity of the distillate at -p— ^ and obtain the correspond- 

 ing percentage of alcohol by volume from 5. 



(b) Grams per 100 cc— From the specific gravity of the distillate, obtained in 

 (a), ascertain from 5 the corresponding alcohol content in grams per 100 cc. 



(C) By weight. — Divide the number of grams in the 100 cc. of distillate, as ob- 

 tained in (b), by the weight of the sample as calculated from its specific gravity. 



(d) By immersion refradometer.— The percentages of alcohol, as determined in 

 (a) and (C), may be verified by determining the immersion refractometer reading 

 of the distillate and obtaining, from 6, the corresponding percentages of alcohol. 



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