469 



which can be effected by an addition of tannin varying from 

 one-eighth to one-sixth ounce per 100 gallons ; aeration and stirring 

 violently to break up the viscosity of the microbes, slight fortifica- 

 tion to bring the strength of the wine to 12 per cent, or more. 

 Pasteurisation will cure the disease in one act. In either case 

 fining and racking is indicated. 



Bitterness is caused by a small, threadlike microbe which, when 



dying, is encased in the colouring matter 



Bitterness Ferment. 



of red wines at the 

 beginning of the sick- 

 ness. The wine de- 

 velops a peculiar dis- 

 agreeable smell, at the 

 same time loses the 

 freshness of its colour 

 and appears more 

 brown. The taste also 

 becomes uneven, flat, 

 sweetish, and is trans- 

 formed into a bitter 

 taste by degrees. Fol- 

 lowing the progress of 

 the sickness the colour- 

 ing matter is entirely 

 lost, and the wine in 

 the end becomes un- 

 drinkable. 



Not only in the cask, 

 but in the bottle, may 

 the wine become bitter. 



Several means have been suggested to cure it 



(i.) Allow a new fermentation with fresh must ; this means 

 only spoiling good must. 



(2.) Racking in strongly sulphured casks checks the progress 

 of the disease. 



(3.) Pasteurising checks it, but, unless carefully done, often 

 spoils the original taste of wine. 



(4.) Fortifying up to 12 per cent. (26 per cent, proof), and a 

 little addition of tartaric acid, will hide the bitter 

 taste. If the disease has gone too far, it is not by 

 any means possible to overcome the bitter taste. 



The use of oxidising substances, such as permanganate of 

 potash, in very slight doses, after previous fortification up to about 

 14 per cent., gives very rapid result. Aeration is also good. After 

 t his, blending with wines of deep colour, and rich in tannin, will 

 restore to the wine its desired equilibrium. 



