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investigations of Pasteur and other French scientists have led to the 

 discovery that the wine "ferments," or "yeasts," are various, 

 according* to the variety of Grape, degree of ripeness, climate, 

 temperature of the must, mode of fermentation, and other local 

 conditions. These scientists also inform us that some of the essential 

 qualities in wines are, to a large extent, dependent upon the character 

 of the fermenting yeast. Under the ordinary system the fermenting 

 agent must necessarily be a matter of chance, whereas it is claimed 

 for the new process that the wine-maker can utilize a special medium. 

 These mediums are selected " yeasts " which are carefully cultivated 

 and preserved, so that they can be applied to wines with certainty. 

 These "yeasts," which are known in French as "levures," are 

 selected from the various classes of notable wines. It is claimed for 

 these artificial ferments that their use ensures wines of more certain 

 character and uniform quality than can be obtained in the ordinary way. 

 Each class of " yeast " is also said to give to a wine a particular and 

 distinctive bouquet, more or less similar to the European wine from 

 which it has originated. As instances the advocates of artificial fermen- 

 tation claim that cultivated " yeasts " of the Pinot Noir of Burgundy 

 and Cabernet Sauvigrion of Bordeaux will to a large extent supply the 

 special characteristics that have made wines from those districts famous. 

 Whether these claims are well founded time and experience must show. 

 It is probable, however, that the advocates of artificial fermentation 

 claim more for the system than results will warrant. Possibly it may 

 prove of great service to wine growers, but it is doubtful whether the 

 system will produce such certain and great results as is claimed for it. 

 It must not be forgotten that the qualities of wines depend upon many 

 factors, and each has a material influence. The "ferment " is only one 

 factor though certainly it is not the least important. It is not likely 

 that by merely using a cultivated " yeast " from a special French or 

 German wine that the products of Australasian vineyards can be made to 

 assume the same characters. Then, again, it must not be forgotten that 

 in using cultivated " yeasts " they must necessarily come in contact with 

 those that form naturally, and possibly results may be materially influenced 

 by this means. Another matter in connexion with artificial fermentation, 

 that will to some extent be a bar to the practice, is the fact that the 

 cultivated " yeasts " must be prepared by skilled scientists, and will cost 

 money. When the system is practised, the first consideration is to use 

 only the special ' yeast " that is suitable for a particular class of wines. 

 As instances, a Bordeaux " yeast " is best suited for Cabernet, Malbeck, 

 and similar kinds. A Sherry " yeast " should be applied to such 

 varieties as Pedro Ximenes and Doradilla, and a Hermitage " yeast " 

 must be used for Shiraz, Grenache, Mataro, and other sorts belonging to 

 the same section. In applying the cultivated " yeasts " they should first 

 be mixed with, say, about ten gallons of sterilised must which ought to 

 be freely exposed to the air for a few hours before it is used in order to 

 encourage active fermentation. The must may be sterilised by heating it 

 to 160 degrees for two or three minutes, allowing it to cool gradually to 

 below 70 Fan. before adding the " yeast." The prepared must is then 



