178 VINEGAR, CIDER, AND FRUIT-WINES. 



by every wine-grower, while for the latter nothing is necessary 

 but a few vessels readily procured. 



Young white wine if attacked by acetous degeneration is also 

 fit for nothing else than the preparation of vinegar. On account 

 of its large content of albuminous substances it is, however, more 

 suitable for the nourishment of the mold ferment than for that of 

 the vinegar ferment, and consequently many difficulties occur in 

 its conversion into vinegar. These difficulties can, however, be 

 prevented by mixing such wine with much air and storing it for 

 some time in barrels filled up to the bung, or heating it after 

 mixing with air to about 140 F., the separation of the albumi- 

 nous substances being effected by both means, though more 

 rapidly by the latter. Before being further worked the wine has 

 to be filtered to remove the now insoluble albuminous substances, 

 whose presence might otherwise give rise to other injurious com- 

 plications. 



Before the appearance of the phylloxera in France and the 

 consequent decrease in the production of very ordinary wines and a . 

 better chance of disposing of slightly sick wines doctored by heat- 

 ing, the manufacture of wine vinegar was extensively carried on in 

 many communities, the sale of this product realizing very large 

 sums. A number of commercial travellers regularly visited the 

 wine-growing districts simply for the purpose of buying up sick 

 wines to be worked into vinegar by the factories represented by 

 them. And, notwithstanding the process of manufacture in general 

 use was rather incomplete, it furnished a highly valued article, 

 though only with a considerable loss of substance. Pasteur made 

 some experiments regarding the mode of manufacture and recom- 

 mended very valuable improvements. 



The question, what constitutes the superiority of wine vinegar 

 over the ordinary product obtained from alcohol, is not difficult 

 for those who have an accurate knowledge of the constitution 

 of wine to answer. Wine, besides the ordinary alcohol (ethyl 

 alcohol), contains very small quantities of other alcohols, for in- 

 stance, amyl alcohol, which, in the same manner as ethyl alcohol 

 is converted into acetic acid, are changed into acids possessing a 

 peculiar odor. Moreover, wine very likely contains a series of 

 odoriferous substances which together produce the peculiar aroma 



