>I was just wondering if it would not be better to feed the bees with fruit juice instead of sugar water? My reasoning is that it should be healthier for them
It is not better for them. Fruit juice will give them dysentery. Just because it is better for a human does not mean it is better for bees. The best is to let them gather nectar. It is what they do. If starvation is an issue, then sugar syrup is next best as it doesn't have solids that they can't handle. A bee's digestive system is not made to digest fruit juice. They will take it, but only if they can't find nectar.