FERMENTATION. 51 



When the summer has been unfavourable, owing to 

 want of heat and excess of rain, the grapes often yield 

 juice which contains less sugar, but a considerable 

 portion of acid, and albumen enough to cause fermen- 

 tation, if only the necessary quantity of sugar were 

 there. 



The desire to obtain, notwithstanding, a serviceable 

 wine, often leads at this stage to an attempt to intro- 

 duce foreign elements into the juice, and to doctor it. 



The simplest plan is to add sugar to the juice 

 which is deficient in saccharine matter : common 

 cane, or beetroot sugar, or on account of its cheap- 

 ness, potiit^e-syrup (glucose) are added, and in 

 sufficient quantities to compensate for the defi- 

 ciency in the juice. So long as the sugar is pure, it 

 matters little whether cane sugar or glucose be em- 

 ployed, since both yield alcohol. 



The admixture with sugar cannot afterwards be 

 detected ; chemistry is here at fault, since only that 

 which was wanting in the fruit has been added to it. 



It is scarcely necessary to mention that wine with 

 an aroma cannot be obtained in this manner from 

 grapes which have ripened badly. Eaisins are often 

 used for the inferior German wines. 



The same means, viz., the addition of sugar to 

 grape juice, are often employed to obtain a stronger 

 wine from good grape juice. In this manner many 

 kinds of strong wine are made to imitate port wine. 



Here, as well as when the juice is sour, much 



