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or substances which are acted upon by the caustic lime in the cane juice 

 and the way in which No. 18 yeast acts upon them to produce an aroma, 

 and I have yet to shew why the effect of the lime is not rendered nugatory by 

 the after addition of sulphuric acid. This however would make my paper 

 too long, and as I am still engaged in investigations on these points, I 

 must defer any explanation for the present. One thing however further 

 experiments have taught me with absolute certainty, that in order that 

 the treatment with lime be efficacious in its influence on the flavour of 

 the rum — and this applies equally, whether 18 yeast is used or not — the 

 skimmings must be thoroughly heated in the syphons after the treat- 

 ment with lime. 



THE JAMAICA YEASTS. 



By Percival H. Greg. 

 In a collection of papers from the Demerara Argosy entitled if I re- 

 member rightly the " Planters Manual" 1889, there is a very interest- 

 ing article on " How to make German Rum, by a Jamaica Distiller." 

 Among other things the author mentions that the liquor throws up a 

 thick golden head, that fermentation is very slow, and that no particular 

 characteristic aroma is produced until after fermentation has been con- 

 cluded. This corresponds so exactly with the behaviour of my No. 18 

 yeast during fermentation that I am inclined to think that the yeast 

 forming the golden head or " Rum fat" as he describes it, is the one 

 which I call No. 18. The author after stating minutely the methods 

 to be employed in the manufacture of this German Rum, confesses that 

 this recipe is not always attended with successful results, inasmuch as 

 that some estates, trying all they can, never produce German Rum, 

 while other estates produce it without any apparent effort. Very in- 

 teresting it would have been if the author had stated, which as far as 

 my recollection serves me he did not, how much importance he attached 

 to the presence of this "ram fat" in producing the aroma, and as to 

 whether this characteristic fermentation was absent or at least not per- 

 manent in those estates which tried to produce German rum, and failed. 

 There would be nothing very startling if this were so. All the 

 most recent researches go to show that the influence exercised by the 

 particular organism active in the fermentations on the flavour of the 

 resulting aroma of the Beer, "Wine or Spirit has up to within recent 

 years been in many cases under-estimated or indeed not taken into 

 account at all. I have seen an organism which out of pure sugar was 

 able to produce liquor which smelt like pure pineapple essence, and I 

 have in my possession, two varieties of the type Saccharomyces ano- 

 malus which produce a distinct pineapple flavour in molasses. Thus in 

 Hansen's Untersuchungen us der Praxis der Gahrungsindiistrie, which 

 translated freely signifies " experiments in practical fermentation," 

 mention is made of the results attained by a Dr. Nathan in Rottweil 

 in the use of selected types or varietes of yeasts in the preparation of 

 fruit wines. The experiments were carried out on a large scale, and are 

 therefore the more important. The conclusion to be drawn from them 

 was that the quality and whole character of the fruit wines, is much 

 more dependant, on the character of the yeast which pla\ s the leading 

 part in the fermentation than is the case with grape juice. If (writes 



