CELLAEING. 113 



so that at least a portion of grape sugar might be 

 formed from tartaric acid. This transformation, which 

 is maintained by Liebig,* has been supposed to affect 

 the sweetening of the wine. All bottled wines which 

 improve at all, become sweeter, and old wines always 

 appear to have gained in sugar. The quantity of 

 sugar cannot increase in weight, but it becomes more 

 evident to the taste when tartaric acid is decomposed, 

 and if the tartaric acid be converted into sugar, it 

 furnishes an additional reason for the increased sweet- 

 ness. 



But this opinion loses all support when we re- 

 member that Berard found t that although the acids in 

 fruit diminished a little during ripening, such dimi- 

 nution was by no means proportioned to the increase 

 of sugar. In some fruits, as cherries and pears, the 

 acids increase, but the sugar increases still more in 

 proportion. 



FremyJ is of opinion that a larger quantity of base 

 saturates the acids in the fruit at the time of its ripen- 

 ing, but Crasso's experiments (p. 17) contradict this 

 assertion. Schubert has tried to prove that the sweet- 

 ening of wine proceeds from a separation of tartar, 

 but this separation cannot be perceived in bottles, and 

 the change we are now discussing takes place in bottled 

 wine. That wine in casks containing a great deal of 



* Journal de Pharm. torn. iv. p. 85, 1844. 

 t Phys. Scheikunde, p. 900. 

 J Journ. de Ch. Med. Mars 1845, p. 132. 

 Pogg, Ann. Bd. 70. 



