Can ants eat sugar that is granulated?

Ants eat anything sweet so yes

My 2nd grade son tested this question for a science fair project. The study design had flaws, admittedly, but what was clear was that given the choice between Splenda, nutrasweet, and various sugars or sugar-containing substances (refined, brown, plum jelly), the ants loved the sugar (especially brown) and early on (around 8 hours) they were collecting around the splenda dish. However, at 12 hours and 24hours after "baiting" the dishes, the ants left the splenda alone! They never really went after nutrasweet - I think this part of the study needs repeating, but it was interesting that the sucralose (splenda) "looks" chemically like sugar, while Aspartame (nutrasweet) is derived from an amino acid. Cool question!

And that was a very cool experiment and observation; congratulations! Firstly, the fact that the aspartame and saccharine are chemically unlike sugar, whereas sucralose is modified sugar and ants behave differently to them, is interesting. Secondly, double-blind experiments with humans, and experiments with animals like rats, show that even convincingly sugar-like non-nutritive sweeteners, though they are at first attractive, tend to lose their attraction fairly soon in the absence of real sugar, much as you saw with the ants and sucralose. In humans, this applied to aspartame and saccharine and other commercial sweeteners as well. So it seems that the way ants taste sweet things is not the same as the way some mammals taste sweet things, and if we needed to make non-nutritive sweeteners for ants some that might not taste sweet to us might be sweet to the ants. Plainly their sugar (sweetness) sensing receptors are not the same as ours. Ants are related to bees, and bees and butterflies are happy to eat and digest octacetyl sucrose, whereas it tastes intensely bitter to humans and monkeys. Probably ants would not mind it and might like it. However, research into taste suggests that even a taste as simple as sweetness just in humans is a very complex subject, and is not yet well-understood.