118 LOUIS PASTEUR 



posit of the wine at the bottom of the casks, but 

 the parasite is not troublesome unless it multiplies 

 very largely. Pasteur found the means of prevent- 

 ing this multiplication by a very simple remedy, 

 equally applicable to other diseases of wines, such 

 as that of bitterness or greasiness (maladie de la 

 graisse). 



Many wines acquire with age a more or less bitter 

 taste, sometimes to a degree which renders them 

 unfit for consumption. Red wines, without exception, 

 are subject to this disease. It attacks by preference 

 wines of the best growth, and particularly the finest 

 wines of the Cote-d'Or. It is once more a little fila- 

 mented fungus which works the change ; and not 

 only does it cause in the wine a bitterness which little 

 by little deprives it of all its better qualities, but it 

 forms in the bottles a deposit which never adheres 

 to the glass, but renders the wine muddy or turbid. 

 It is in this deposit that the filaments of the fungus 

 float. If white wines do not suffer from this disease 

 of bitterness, they are exposed, particularly the white 

 wines of Orleans and of the basin of the Loire, to the 

 disease of greasiness. The wines lose their limpidity ; 

 they become flat and insipid and viscous, like oil when 

 poured out. The disease declares itself in the casks or 

 in the best-corked bottles. M. Pasteur has discovered 

 that the greasiness of wines is likewise produced by a 

 special ferment, which the microscope shows to be 



