88 FERMENTATION. 



ment are therefore acid phosphate of potash, neutral 

 phosphate of potash, phosphate of magnesia, and phos- 

 phate of lime. 



Prom what has been said about the composition of 

 wine ferment, it is sufficiently evident that it does not 

 essentially differ from beer ferment, for both consist of 

 membranous cells which are formed out of gum, or 

 vegetable mucilage. Both possess albuminous contents, 

 which exude through the walls of the cells, and when 

 brought into contact with sugar, cause it to ferment ; 

 these contents are soluble in water, more so in vegetable 

 acids, and peculiarly so in tartaric acid. So much of 

 the albuminous substance as is soluble is decomposed 

 during fermentation, and more or less of its products 

 must be contained in the liquid. 



ON THE DIFFERENCE BETWEEN THE CONSTITUENTS OF 

 GRAPE JUICE AND THOSE OF WINE, CONSIDERED IN 

 CONNEXION WITH FERMENTATION. 



The formation of ferment diminishes the gum or 

 vegetable mucus in the grape juice, and renders it 

 insoluble, in which state it composes the walls of 

 the ferment cells, and the juice becomes turbid. 

 In this manner vegetable gluten and vegetable 

 albumen (substances contained in the grape pulps) 

 are withdrawn from the juice, and enclosed in the 

 cells. But during the decomposition of ferment, 



