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So I'm trying to figure out how to titrate the reducing sugars on honey without generating iodine.

The reaction so far I think I could do is do a Fehling reaction with $\ce{Cu}^{2+}$and then back-titrate the remaining with EDTA, but I'm not sure that the EDTA wouldn't solubilize the $\ce{Cu2O}$, or be able to displace the tartrate.

Some sources I've looked say that this can be done as a direct titration using methylene blue as an indicator, but they haven't given a pH range, even if the reaction is fast enough to be done as a direct titration.

Any thoughts?

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The usual titration of glucose with Fehling's Reagent is to place the Fehling's Reagent in a flask and titrate the boiling solution with glucose. At the end point, all the $\ce {Cu^{2+}}$ ions are converted to $\ce {Cu^{+}}$; this makes the solution colorless. That is difficult to see since the red copper(I) oxide is floating in the solution.

With methylene blue, after the copper has been reduced, the glucose can then reduce the methylene blue (in a basic solution) to a colorless solution. This makes the end point clearer since the methylene blue is much darker than the $\ce {Cu^{2+}}$ ions. The pH of the solution does not change much in this reaction.

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