Storing of Vinegar 471 



Apart from the possible elimination of the vinegar 

 eels, all of the old uncertainty as to results accompanied 

 this method, and led to its abandonment. On the other 

 hand, the use of pure cultures proper promises to gain 

 favor with vinegar-makers. The difficulties involved 

 are not at all insurmountable, and, as laboratory ex- 

 periments have shown, pasteurization at comparatively 

 low temperatures may be employed to assure the estab- 

 lishment of the desirable ferments. 



The storing of vinegar. — The vinegar itself, like 

 souring wine or cider, is liable to deteriorate on standing. 

 Stored vinegar, as is well known, may lose its flavor, 

 or may become turbid or sUmy. The same undesirable 

 organisms that become prominent in the process of 

 vinegar-making may become prominent also in the 

 manufactured vinegar, especially in the home-made 

 product. Practical experience teaches us that the de- 

 terioration of stored vinegar is most marked when the 

 proportion of acetic acid in the liquid is least. 



Careful investigations have demonstrated that the 

 vinegar eel multiplies only when the proportion of acid 

 falls below 6 per cent. When more than this quantity 

 is present, the growth of vinegar eels is suppressed. 

 Similarly, the acid-consuming yeasts are not allowed 

 to multiply when the proportion of acid exceeds 3 per 

 cent; frequently their growth stops even when the quan- 

 tity of acid is only 2 per cent of the entire volume. 

 On the contrary, the acetic-acid bacteria are much more 

 resistant to large accumulations of acid, some of them 

 continuing to grow when the acid content reaches 11 

 per cent. Losses of acetic acid may occur under these 



