Is it important that I use crystal sugar from the same source in my experiment?

[ZuzaMagda]

Is it at all possible for the crystal sugar from one package to be qualitatively different from crystal sugar from another package (brand, etc.)? In other words, if I need sucrose for an experiment, could it affect the results if I use crystal sugar from different packages or of different brands? What if I use sugar that was bought ten years ago and sugar that was bought recently? Does sucrose "get old" at all?

 

[fss]

Yes, it is possible. If the sugar is not supposed to be a variable, you need to try to keep it as much of a control as possible. Same batch is a good idea.

 

[ZuzaMagda]

But why? How exactly could sugar from different batches affect the results of my experiment?

I mean, for all I know, crystal sugar is basically sucrose, and sucrose is sucrose, or C₁₂H₂₂O₁₁ if you like. If you use distilled water - pure H₂O - in an experiment, I don't think you worry much about whether you are taking it from the same bottle every time or even if you are using the same brand, do you?