process. He allowed a mixture of hydrolyzed cane sugar, cheese, sour
milk, and calcium carbonate to undergo spontaneous fermentation
for 2 or 3 months. From the fermented mass he isolated mannitol in considerable
quantities; e.g., 1 pound of pure mannitol from the fermentation
of 10 pounds of sugar. Dragendorff repeated the earlier work of Strecker
and obtained a good yield of mannitol in his first fermentation, but a
second experiment failed to show a trace of mannitol.
In the course of a discussion on the causes and conditions of lactic acid
production Pasteur pointed out that besides lactic acid, other products,
such as alcohol, butyric acid, and mannitol, were formed. He noted that
great variations occurred in the amount of mannitol produced.
Marcano in the making of rum from the sugar-cane of the West Indies
recognized mannitol as a product of the fermentation.
In all this early work no attempt was made to use pure cultures of
bacteria or pure chemical substances.