You should have horses like the two I have now. They won't eat apple. Put it in their mouth and they'll drop it out. They don't like candy either. In the beginning I had great fun with the ladies at the stables who bring apples and mints as treats for their horses. They'd ask if they mine could have one and I say sure, but they won't eat it. They wouldn't believe me until they tried. One girl did get my youngest mare to take a mint one day and was all excited because she took it and immediately bit it as she took it and the girl happily said.."see, she likes it" as the horse immediately after biting let the two pieces dropped to the ground and she was licking her tongue around like she was trying to get rid of the taste
Did get one of them to eat a bit of carrot once, but normally they won't eat that either. Their idea of a treat is some hay pellets. They'll eat those like it's horse candy. Of course if I could compress their copra into pellets they'd probably walk on hot coals for it. I believe the oldest would charge the gates of hell if she thought she there was a bucket of copra on the other side for her. I've never seen horses love a feed so much, but oh does it put weight on them.
But I digress (nothing new there
). Apples. As already mentioned there's not a difference between the sugar (we'll call it sugar for this purpose
). There are some differences between some apples, but it has more to do with the specific type and not the color. Most green apples are tart, so the acid that does that tends to make them seem less sweet (same with tart red apples). Horse, like people will have preferences (I like mine that don't care for apples).