Process for the treatment of an aqueous sugar solution in order to isolate and separate the saccharides having a cetonic function.

摘要

Process for the treatment of aqueous sweet juice containing a mixture of saccharides containing an aldehyde functional group, especially fructose, and saccharides containing a ketone functional group, especially glucose, with a view to separating and selecting the saccharides containing a ketone functional group. It consists (a) in making up a hydroorganic medium by mixing the sweet juice with a ketonic compound containing active methylene, a calcium-based catalyst and preferably ethanol, (b) in stirring the medium until the formation of furane-based polyol by condensation of the ketonic compound and the saccharides containing an aldehyde functional group, and (c) in allowing the furane-based polyol to precipitate and separating it off by a physical route from the liquid medium; the latter is completely freed from the saccharides containing an aldehyde functional group. The process of the invention makes it possible, in particular, to prepare pure fructose syrups.