274 MICRO-ORGANISMS AND FERMENTATION. 



interesting instance of the energetic action of certain types of 

 wine-yeast is supplied by the extensive production, in the 

 Scandinavian countries, of wine prepared from raisin juice but 

 fermented with genuine wine-yeast. 



In addition to the quotations made above, the following 

 statement by Professor J. WORTMANN, director of the pure 

 yeast-culture station of the German Association for Viticulture 

 at Geisenheim, may be given : 



" If, with a view of throwing light on the general results 

 obtained in practice, we sum up the main contents of the 

 reports, we shall find at once that wherever pure yeast can be 

 employed in such a manner as to be without a rival from the 

 very beginning in other words, wherever the desired fermen- 

 tation can easily be carried out in practice by the exclusive 

 use of the pure yeast added a favourable effect of the pure 

 yeast is in all such cases unmistakable. This is especially true 

 of the fermentations carried out in the preparation of sparkling 

 wine, and of the renewed fermentations of wines. But in 

 these cases we also find and this point is most important 

 that we are in the right track regarding the method adopted 

 for the use of the yeasts, since it has led to such good results 

 even in these first experiments. 



" Further, we are sure, judging from the results so far 

 secured, to obtain satisfactory effects with pure yeasts in all 

 those cases in which musts of little value or fruit- and 

 berry-musts are fermented. The yeasts present in fruit- 

 and berry-musts are presumably apiculate or other dangerous 

 forms, and are soon overcome by a vigorous pure yeast, but 

 apart from this we have it in our power to utilise the type of 

 yeast adopted to the best advantage, for owing to the repression 

 of the bouquets peculiar to such musts, the peculiarity of the 

 pure yeast will become more prominent, especially with regard 

 to bouquet-formation. 



" In the fermentation of grape-musts with pure yeasts, owing 

 to the fact that yeasts, contained in the musts themselves, are 

 very vigorous and efficacious, under the circumstances we can 

 only expect to secure success if it is possible to bring the pure 

 yeast into the must in such a manner that it predominates at 

 the outset over the yeasts already present. This is a conditio 



