PREPARATION OF THE ALCOHOLIC LIQUID. 107 



the fact that the more freight has to be paid on what is of no 

 value, the weaker the vinegar is, and that the expense of trans- 

 porting a strong article is relatively less, deserves consideration. 

 The consumer can readily prepare vinegar of any desired strength 

 by diluting the strong product with water. 



The quantity of beer required for the purpose of offering suit- 

 able nourishment to the vinegar ferment is very small, an addition 

 of 1 per cent, to the alcoholic liquid being ample. Sour or stale 

 beer can of course be used. The reason for the employment of 

 larger quantities of beer in mixing the alcoholic fluids is found 

 in the fact that the vinegar prepared from such mixtures sooner 

 acquires a pure taste than that made from fluids containing but 

 little beer. The addition of beer should, however, not exceed 15 

 per cent, of the total quantity of alcoholic liquid, as on account 

 of the comparatively high percentage of albuminous substances 

 and the maltose, dextrin, and extractive matters of hops it con- 

 tains, a larger quantity would be injurious to the process of acetous 

 fermentation, the generators being frequently rendered inactive by 

 the so-called " sliming of the shavings." The production of the 

 latter is due to the fact that by being partially excluded from 

 contact with the air by the comparatively thick fluid passing over 

 it, the vinegar ferment deposited upon the shavings assumes the 

 form of mother of vinegar which adheres to the shavings as a 

 slimy mass. 



The quantity of finished vinegar added to the alcoholic liquid 

 varies between 10 and 33 per cent. The use of large quantities 

 is, however, decidedly inexpedient since. the only effect produced 

 by the vinegar is, as previously stated, due to the ferment con- 

 tained in it. Of freshly prepared, turbid vinegar 10 per cent, is 

 ample for the preparation of alcoholic liquid ; a greater quantity 

 can only be considered as useless ballast. 



Theoretically a certain quantity of alcohol yields exactly a 

 certain quantity of acetic acid ; the following table shows the 

 proportions between the two bodies : 



