FERMENTATION WITH SPECIAL REFERENCE TO THE SUGAR HOUSE. 



Foaming of Massecuites. Geerligs 16 explains the foaming of 

 stored massecuites as due to the spontaneous decomposition of glucinic acid 

 formed by the action of lime on reducing sugars. Ashby, 17 however, has in 

 Jamaica isolated a yeast which is active in concentrations up to 80 Brix, and 

 attributes the phenomenon to the presence of these organisms. 



Faulty Hum. By faulty rum is meant a spirit which on dilution 

 with water becomes cloudy and throws down a deposit. The causes to which 

 this behaviour are attributed are : The presence of caramels soluble in strong 

 and insoluble in dilute spirit ; the presence of higher fatty acids, due to 

 careless distillation, which are precipitated on dilution; the presence of 

 tcrpenes extracted by the spirit from the casks ; the presence of a micro- 

 organism capable of life and reproduction in 75 per cent, alcohol; the latter view 

 was brought forward by Y. H. and L. Y. Yeley 18 who named the supposed 

 organism Coleothrix methystes and stated that it is extremely resistant to ordinary 

 methods of destruction, survives desiccation, is air borne, and both aerobic and 

 anaerobic ; in certain of their publications the organism is described as multi- 

 plying and living actively in 75 per cent, rum and in other places as merely 

 surviving in spirit. The whole of the results of Y. H. and L. Y. Yeley were 

 challenged by Scard and Harrison, 19 who were unable to obtain any of the 

 effects noticed by the Yeleys. They found, however, in Demerara rums 

 remains of organisms similar to the one in question, and were of opinion that 

 faultiness in rum was due to the first three causes mentioned above. 



When rum samples have been kept in an imperfectly sealed bottle so that 

 the spirit is free to evaporate, the writer has frequently noticed a slimy 

 mucinous growth appear ; this on microscopic examination is found to be of 

 a fungus character, and to be similar to that described by Yeley as the cause 

 of faulty rum. The writer has never observed it in strong spirit, but when 

 the fungus growth was transferred en masse to 75 per cent, alcohol, the 

 organisms were not killed but cultures could be obtained for over a year ; 

 the growth did not increase in size but remained suspended in the rum, 

 which remained quite clear ; when a drop of the original weak spirit con- 

 taining the fungus was inoculated into sound clear rum, no change whatever 

 took place. The writer thinks it quite possible that masses of the organism, 

 to the existence of which he gives credence, have found their way into casks 

 and puncheons, and have thus been present and alive on arrival in England, 

 but does not think they can be called the cause of faulty rum. 



Deterioration of Sugars. The deterioration of sugars on storage 

 is without doubt to be attributed to the action of micro-organisms. Shorey 10 

 attributed it chiefly to the action of mould fungi, but more recent studies lead 

 to the conclusion that bacteria are mainly responsible. Grieg Smith 20 was 

 inclined to attribute the damage to one specific organism, Bacillus 

 levaniformans, which he found originally in Australian juices and sugars 

 and afterwards in sugars of cosmopolitan origin ; this organism is char- 



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