56 WINE AND THE ART OF WINE TASTING. 



trifle, and that the presence of the "flowers" excluded the action of 

 other micro-organisms. 



We must not, however, reason from this that the Mycoderma- vini is 

 really of use, for if exposure to the air should happen, if, instead of 

 remaining white, the " flowers," as Pasteur noticed, should turn red, 

 then, sooner or later, it will cede its place to other organisms, to the 

 vinegar diplococcus, which, as I have shown before, is ready immedi- 

 ately to commence action, finding itself in favorable condition for its 

 development, for the "flowers" itself serves for nutriment; and if 

 there should be a considerable rise in temperature, the conditions are 

 the best possible. 



The final conclusion then, plainly is, that the " flowers " should be 

 carefully guarded against; this is done by the strictest attention to "fill- 

 ing up," the importance of which was recognized by the poet Alemann, 

 when he wrote: 



Che nulla cos a 

 Pub medicar il vin, che resta scemo. 



The " flowers " may be destroyed by the addition of sulphurous anhy- 

 dride or a few drops of alcohol. 



With wine in bottles, the development of the "flowers" is prevented 

 by keeping the bottles lying down; if instead the wine is kept in flasks 

 ("^asc/w"), as in Tuscany, or in demijohns, a few drops of the purest 

 olive oil on the surface of the wine will have the same effect. 



SOUR, PRICKED, ACETIFIED ( Vino die ha preso il fuoco, Lo spunto, La 

 punta, II portore, Vino acetoso, It.; Vin qui a pris le feu, VAigre,T?r.). 

 Acetic acid is one of the normal components of wine. It is formed 

 during the alcoholic fermentation, but in such minute quantities as to 

 be imperceptible to the taste. When the proportion of this acid, from 

 one of the many known causes, becomes large enough as to be percepti- 

 ble, then the wine is said to be "pricked." 



A pricked wine retains its natural color and limpidity. 



This defect is recognized by the odor and taste of acetic acid; in tast- 

 ing, its strongest effect is perceived at the base of the tongue. 



If a wine thus affected is not taken in hand immediately (and in 

 truth success is not always sure) and treated with heavy sulphurings 

 or pasteurizing, it soon becomes sour and acetic. 



Acetification is due to the action of a micro-organism, the bacterium 

 known under the name of Diplococcus aceti, still commonly called Myco- 

 derma aceti, which increases with a rapidity truly prodigious. Ducleaux 

 tells us that if on a surface of wine a metre square an almost impercep- 

 tible amount of these bacteria is allowed to fall, in twenty-four hours 

 the whole surface of the liquid will be covered with a layer of them so 

 closely placed as to be crowded into contact. Thus, there will be three 

 hundred thousand million individuals formed in twenty-four hours. 



The rapidity with which the acetic bacterium multiplies explains why 

 a pricked wine, when the temperature is favorable, becomes so quickly 

 completely acetified. 



It should be remembered that whilst it is easy to prevent this disease 

 by taking proper precautions in the fermenting-room and cellar, it is 

 difficult, if not impossible, to destroy it when started. 



Once a wine has become pricked, instead of trying to effect a cure, it 

 is better to follow the advice of Guyot, who says: 



" When wine acquires the odor and taste of acetic acid, it is sent to 

 the vinegar factory, but it is never attempted to use it as wine." 



