98 CLEAKOSTQ OF WINE. 



precipitating tannate of gelatine and colouring matter. 

 In some countries extract of grape stones, which, as we 

 have seen (p. 44), contain a large proportion of tannic 

 acid, may be used instead of nut-galls. 



Clearing, as a general rule, makes wine more 

 durable ; but when isinglass or albumen have been 

 employed, this is not always the case. Burgundy 

 wines, which are readily decomposed, are often rendered 

 more easily decomposable in consequence of clearing. 

 Por Burgundy wine contains but little tannic acid, 

 and the process of clearing, by freeing it still more 

 from this, removes at the same time the ingredient 

 which would have rendered inert the albuminous sub- 

 stance of the wine. 



Too large an admixture of solution of gelatine, or 

 albumen, brings the germ of decay into the wine which 

 is cleared ; since they are both organic bodies, easily 

 putrescible, and capable of exciting decomposition in 

 other substances. 



If too much gelatine or albumen has been added, 

 Vergnette Lamotte recommends the use of a little 

 tannic acid. Bussy,* speaking of the clearing of 

 Burgundy wine, urges the application of extract 

 of nut-galls to the wine, before gelatine is used. 

 Before this method was known, it was impossible to 

 render Burgundy quite clear without exposing it too 

 much to the chance of spoiling, since all the tannic 



* Moniteur Industriel, 1848, No. 1300. 



