54 VITIS, OR 



9. Wine making is a chemical operation, in which a 

 due proportion of needful elements is essentially requi- 

 site. No liquor is a wine unless it has undergone the 

 real vinous fermentation. 



10. The needful elements of fermentation are, 1. Su- 

 gar. 2. Water. 3. Tartaric acid. 4. Mucilage. The ad- 

 ventitious elements, which may or may not exist, are 

 tannin, potash, carbonic and malic acids, arome, color- 

 ing principle, &c. 



11. The Must is the liquor produced by grapes. A 

 perfect Must ought to have a due proportion of the four 

 elements of wine. When deficient in any, it ought to 

 be supplied, if we want to make good wine. If any ele- 

 ment is in excess, it ought to be corrected. 



12. The due proportion of sugar or sweet principle, is 

 3lb. in one gallon of Must. When less, the Must makes 

 a very dry or weak wine, when more, a very svveet 

 wine. The sugar is changed by fermentation into alco- 

 hol, chemically combined in the wine, and only evolved 

 as a vapor by fire or the process of distilling. In all 

 sweet wines, a portion of the sugar is not decomposed, 

 still more involving and weakening the alcohol. 



13. The due proportion of tartaric acid and mucilage 

 does not exceed 5 per cent, of each. The excess of tar- 

 taric acid makes the wine sour or acid. When deficient, 

 or supplied by malic acid, the wine is deficient in body 

 and strength. Malic acid changes wine into cider li- 

 quors ; grapes have little malic acid, whence best to 

 make wine. 



14. Currants, gooseberries, blackberries, apples, &c. 

 containing too niuch malic acid, and no tartaric acid, can 

 never make but bad and sharp cider wines by them- 

 selves ; but by the addition of quicklime, the acid is 

 absorbed and corrected, the tartaric acid may be sup- 

 plied ; water dilutes the juice, and sugar strengthens it, 

 whereby imitation wines are made. 



15. When mucilage is deficient, no due fermentation 

 can take place. The substitution of yeast spoils the 

 wine, and gives to it the flatness of beer. Mucilage is 

 rather to be supplied by dissolved gum, in case of need. 

 An excess of mucilage produces only a greater quantity 



'r^vj. 



