BY R. GREIG SMITH. 679 



80% was converted into sugar by heating for three hours at 

 80° C. with an amount of lactic acid equal to that found in the 

 cultures. 



The deterioration of Hawaiian raw cane sugar was investigated 

 by Shorey"^ about three years ago. In the paper he mentions that 

 one of the reasons put forward to account for the inversion of 

 the sugar is a fermentation caused by bacteria, prominent among 

 which are those producing lactic and butyric acids. At another 

 place he writes : — 



" It is generally accepted that the butyric ferments are without 

 the power of inverting cane sugar, while the lactic ferments some- 

 times seem to have this power. It seemed to me, however, very 

 unlikely that the inversion could be brought about by bacteria. 

 The sugar was quite dry, the crystals separate and distinct, and 

 in appearance was like so much air-dried sand. Even in Decem- 

 ber, when the deterioration had reached 4*0°, although the sugar 

 was moist, each crystal was still separate and distinct, being 

 simply coated with a thin syrupy film. Bacteria can only reach 

 development in a liquid or semi-liquid continuous medium, and 

 sugar, so long as it continued so dry that the crystals remained 

 distinct and separated by air spaces, would necessarily prove a 

 medium ill-adapted for the growth of such bacteria as produce 

 lactic or butyric acid. Moreover, all the sugars examined showed 

 as the result of deterioration a very small amount of acid and a 

 comparatively large amount of invert sugar. Now if lactic acid 

 ferments were the invertive agents, the processes of inversion and 

 production of acid would undoubtedly go on together or so closely 

 that they would seem simultaneous. I was led to conclude then 

 that the inversion was not produced by lactic or butyric ferments, 

 but by some other agent." 



Shorey did not search for bacteria, but he discovered the 

 mycelia of Penicillium glaucum distributed among the cr^^stals, 

 and concluded that this ubiquitous mould was the active inverting 

 agent in the particular samples. 



'■• Shorey, Journ, Soc. Chem. Industry, xvii., 555. 



