CANE SUGAR. 



In consequence of an abortive prosecution for selling Demerara rum as 

 Jamaica rum, Harrison 29 examined the ethereal salt content of Demerara rums, 

 finding a variation from 23'7 to 141*6, with a mean of 64'7 parts per 100,000 ; 

 pot still rums contained on an average 69'9, and continuous still rums 44*9 

 parts per 100,000 of alcohol. 



In Jamaica rums, classed as common clean/ Cousins 30 found 200-300, 

 in high-class ordinary rums 300-400, and in the best flavoured 1100 and 

 upwards parts ethereal salts per 100,000 of alcohol. 



The Flavour of Rum. It is generally held that the peculiar fruity flavour 

 of rum is due to the presence of ethyl ethers, particularly the butyrate and 

 caprylate. It has been shown by Cousins that these ethers, particularly the 

 latter, are present in very minute quantity, and that the ether predominantly 

 present is the acetate; compared with the other ethers the acetate and butyrate, 

 particularly the former, are volatile and these serve as a means whereby the 

 heavier ethers are conveyed to the organ of smell. According to the same 

 writer the accentuation of the flavour on dilution is due to the presence of 

 water decreasing the volatility of the acetate thereby masking its somewhat 

 pungent yet pleasant smell. These remarks apply exclusively to Jamaica rums, 

 and not to Demerara rums of less ether content ; in these Harrison"* 9 claims 

 that the peculiarities are in some part due to the caramel compounds used in 

 colouring. 



The origin of these ethers is connected with the process of manufacture 

 followed ; Allan 31 considers that the factors are the presence of fission yeasts, 

 of butyric acid forming bacteria, of which he has isolated one, and of Bacillus 

 mesentericm, to which is attributed the presence of higher alcohols, especially 

 butyl alcohol ; Allan's work refers to Jamaica rums, and bacteria could play 

 only a very small part in the development of flavour in the quick fermentation 

 process followed in Demerara, where indeed bactericides are used to inhibit 

 their action. 



That the budding yeasts have but little to do with the development of 

 flavour in rum is probable from the results of Peck and Deerr, 5 who found in 

 pure culture that only 18 parts of ether (as acetate) were formed per 100,000 

 of alcohol, and previously Deerr had observed no special flavour when cultiva- 

 ting in pure culture fourteen Demerara yeasts ; with the fission yeast Peck and 

 Deerr isolated from Peruvian material no special flavour was observed ; from 

 Natal material they obtained, however, a Monilia, which produced a slow 

 alcoholic fermentation, and at the same time formed 7558 parts ethereal salts 

 (as acetate) per 100,000 of alcohol, both acetate and butyrate being present; to 

 this or to a similar organism they suggested the origin of ethers in high-class 

 rums. About the same time Ashby 32 found a ' fruit ether producing yeast ' in 

 Jamaica distilleries. Micko 27 by means of fractional distillation has established 

 the presence in Jamaica rum of a body which is not an aldehyde, ketone or 

 ester, but has the properties of an ethereal oil, though it may be allied to 



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