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When a bottle of sports drink that contained sucrose is opened, is it expected that the sucrose contained therein will split into its constituents (fructose and glucose) more rapidly than it will via acid hydrolysis?

I understand that in acid hydrolysis there is nucleophilic substitution (provided the acid is protic). Does a similar phenomenon occur when the contents of the bottle are exposed to oxygen?

I am trying to interpret some unexpected results I obtained from an experiment, and I assume what I have detailed here is what happened. However, I cannot find any relevant information to confirm or deny my hypothesis.

RESULTS:

The experiment showed 0.72 g of glucose was present per 100 mL of solution. The bottle label states that it is 0.5 g per 100 mL.

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  • $\begingroup$ Hmm, there might exist reaction that is catalyzed by O2 but generally it doesn't catalyze anything imo $\endgroup$ – Mithoron Aug 20 '15 at 0:55
  • $\begingroup$ The manufacturers are allowed to round their numbers. $\endgroup$ – LDC3 Aug 20 '15 at 1:01
  • $\begingroup$ Acid present in drink could catalyse hydrolysis of sucrose $\endgroup$ – Mithoron Aug 24 '15 at 15:39
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If any sucrose hydrolysis were occurring due to oxygen as a factor, it's more likely due to acids formed as it oxidizes species in the solution (for example, alcohol groups to carboxyls), which conceivably could include sucrose itself. But, it seems more likely that the $\ce{CO2}$ in air would be a factor because $\ce{CO2}$ dissolution increases the acidity of the solution, in addition to any other acids present (citric, for example).

However, sucrose hydrolysis is really slow unless the acidity and/or heat is significant ($\mathrm{pH} < 0$, or heat near boiling), so I doubt either of these explanations, unless these are really old, and/or had been heated. More likely the glucose was there in the first place.

The way to properly answer this question would be to do control studies in which known amounts of sucrose and acid are initially present and tested with or without exposure to air having varying amounts of oxygen and carbon dioxide.

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