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liere an intentional lactic acid fermentation in the yeast-mash is caused, 

 in order that the antiseptic properties of the lactic acid which is formed, 

 may protect the yeast from hard usage at the hands of other bacteria. 

 After a sufficient amount of lactic acid has been produced however the 

 lactic acid bacteria are killed, or at least rendered " hors de combat} 9 

 by warming the yeast-mash up to 60° Reaumur. The mash or "wash" 

 which serves for fermentation is also rendered sterile for all practical 

 purposes by conducting the " saccharification process" at a comparatively 

 high temperature, so that here again the desired type of yeast has 

 the field practically to itself. But in the case of the fermentation of 

 sugar cane juice the case is somewhat different. If we wish to 

 give ourselves an idea of the results to be expected in the application 

 of selected types of yeast in the fermentation of fresh cane juice, we 

 must examine the results obtained in the application of this system in 

 the preparation of wine, i. e., in the fermentation of the juice of the 

 grape. 



Grape juice and cane juice possess the property in common of enter- 

 ing into fermentations " spontaneously" — if left to themselves they be- 

 gin to ferment without the addition of yeast. 



Pasteur proved many years ago, see " Studies on Fermentation," an 

 English edition of which is published by Macmillan & Co. London, that 

 this was caused by the yeast cells which are found adhering to the 

 skin of the grape, and on the crushing or squeezing of the grape 

 come into immediate contact with the juice, and cause it to ferment. 

 [Recent researches have shown that the same process obtains by the cane. 

 "We can easily see therefore, that in order to obtain successful results, 

 we must either get rid of the yeasts naturally present in the cane juice, 

 or we must be certain in advance that in innoculating the juice with 

 such and such a }^east, that we do it with that particular yeast which is 

 absolutely adapted for the work it has to perform and which will find 

 the medium in which it has to ferment in a'l respects a suitab'e one. If 

 . not, then we run the risk, that the struggle for existence which 

 invariably ensues will ultimately end in " the survivel of the fittest," 

 which may not perhaps give the kind of fermentation we desire. The 

 following translation of an abstract of a lecture by Julius Wortmann, 

 delivered before the 13th Congress of the Wine Trade in Mainz may 

 prove interesting. This article is taken from the " Centralblatt Mr 

 JBakteriologie und Parasitenkunde," and the title of this article is 

 (translated). "The practical results obtained up to the present time with 

 pure yeasts, and the practical lessons to be learnt with regard to the 

 selection and application of the same." 



" While the brewing and Spirit- Making industries have long ago 

 made use on a practical scale, of the favorable results which were 

 obtained in the Laboratory by Hansen's system of fermentation, it is 

 only lately that these magnificent results have attracted the attention 

 of those engaged in the manufacture of wine. It is but a few years back 

 that the first attempts were made, to ferment grape juice by selected 

 yeasts from the Laboratory. Up to then no attention had been paid to the 

 yeast in grape juice fermentation, which was simply brought about by 

 means of impure races of yeast which were derived from the grapes to 

 which they were fortuitously attached. Such a fermentation by means 

 of these races of yeast of unknown source, along with the simultaneous 



