CLEARING OF WINE. 99 



acid was withdrawn, and very often replaced by 

 gelatine, or albumen. An addition of tannic acid is 

 also recommended in the case of those white wines 

 which occasionally become "lang," what the French 

 call "graisse." Tannic acid tends to produce stabi- 

 lity by combining with the small quantity of albu- 

 minous matter which is found in the wine, and which, 

 though not thereby made insoluble (as is the case in 

 tanning leather), since the tartaric acid keeps it in 

 solution, is yet rendered less susceptible of decom- 

 position, j 



Only the best isinglass, such as is thoroughly taste- / 

 less, should be made use of in clearing wine. 



Blood is now and then used instead of albumen ; ^ 

 and in a low temperature dried blood, which is sold 

 as powder, is occasionally employed. But none of 

 these means are applicable to good wines. 



Milk and cream may also be used as clarifiers, 

 since the caseine contained in milk combines with the 

 tannic acid of the wine, and acts in the same manner 

 as albumen or isinglass. 



Some, whilst clarifying with albumen or isinglass, 

 add a little common salt to the wine, a proceeding, 

 however, which is said by Batillat * to be useless. 



If lime be mixed with wine in order to abstract 

 tartaric or acetic acid, a precipitate is formed in the 

 first instance, which carries down a larger or smaller 

 portion of the colouring matter of the wine (if red). 



* Mon. Industr. p. 101. 



