MUCINOUS FERMENTATION AND INVERSION. 277 



ducts of the decomposition (preceded by inversion) of cane-sugar 

 by this organism are mucus and amyl alcohol. The former is 

 identical in properties with dextran, and is soluble in warm dilute 

 acids and alkalis, but insoluble in baryta water or milk of lime. 

 An acid odour is evolved during this fermentation, but no lactic 

 acid is formed. 



The number of species of bacteria capable of interfering with 

 the normal course of sugar manufacture is by no means exhausted 

 with the examples mentioned above, but owing to the paucity of 

 observations on this point no further reliable particulars can as 

 yet be given. Consequently the subject presents an admirable 

 field for bacteriological research in order to elucidate the causes 

 and prescribe remedial measures for mucinous fermentation. It 

 is well known to sugar-makers that the percentage of invert sugar 

 in molasses increases during storage (sometimes for months) in the 

 so-called reserves, and they are also aware of the decomposition 

 occurring in stored raw sugar and resulting in the formation of 

 invert sugar. Now the faculty of excreting an inverting ferment 

 is not very widespread among bacteria. For a comprehensive in- 

 vestigation on this point we are indebted to C. FERMI and G. 

 MONTESANO (I.), who examined about sixty (some of them patho- 

 genic) species of bacteria, but found only four, viz., Bacillus 

 megatherium, Bacillus fluorescens liquefaciens, the red Kiel Bacillus, 

 and Proteus vulgaris, capable of producing invertin in saccharified 

 bouillon. Experiments which have been made by A. HERZFELD 

 and U. PAETOW (I.), on the prevention (by hydrofluoric acid and 

 alkali fluorides) of inversion in molasses, lead to the hope that 

 these antiseptics may prove useful in many cases. Further re- 

 searches on this subject are highly desirable. The nitric fer- 

 mentation of molasses will be briefly mentioned in Chapter xxx. 



Sugar-juice and raw sugar are occasionally infested with higher 

 fungi as well as with bacteria. For instance, A. HERZFELD (I.) and 

 A. B. FRANK (I.) report the occurrence of a red pigmentary fungus 

 in raw sugar. They found (in an after-product) red lumps, about 

 as large as hazel-nuts, which, under the microscope, proved to be 

 abundantly infested with a thread fungus, the protoplasm of which 

 was stained by a red pigment, presumably generated by the bac- 

 teria present in large numbers in the mass. The development of 

 pigment bacteria is also frequently noticeable in the saturation 

 scum thrown out from the sugar-works and spread over the fields, 

 this scum being often found covered with coloured (mostly red) 

 patches, which are presumably zoogloea of Micrococcus prodigiosus. 



Large though the number of injurious fission fungi in sugar 

 may be, it is surpassed by the multitude of Eumycetes infesting 

 the sugar-beet. These, however, do not fall within our province, 

 and readers who may be interested in them are referred to the 

 various text-books on plant diseases. The works compiled by 

 A. B. FRANK (II.) and P. SORAUER (II.) respectively, presuppose 



