It also yields, by the so-called mucous fermentation, a mucous, gummy mass, mixed with mannitol and lactic acid.
The starting point was ordinary(d)mannite (mannitol),C 6 H 14 0 61 a naturally occurring hexahydric alcohol, which only differed from a-acritol, the alcohol obtained by reducing a-acrose, with regard to optical activity.
The ketone is also obtained when Bertrand's sorbose bacterium acts on glycerol; this medium also acts on other alcohols to yield ketoses; for example: erythrite gives erythrulose, arabite arabinulose, mannitol fructose, &c.
The micro-organism splits up the laevulose in the must, forming mannitol and different acids, particularly volatile acid.
It would appear from the researches of the author and others that the mannitol ferment is more generally present in wines than is supposed to be the case.
In these cases the mannitic fermentation had obviously not developed to any extent, and small quantities of mannitol appear to exercise no prejudicial effect on flavour.