Are they using the American Fanta recipe or the European Fanta recipe? The European recipe uses fruit juice and the American one uses artificial flavoring.
just from the taste, i am certain (in the strawberry fanta at least) there was nothing even remotely resembling real juice. i think the ingredients list confirms that, but i'll have another look at lunch today. anyway, the classic orange fanta wasn't bad at all, so i might take a look at that again as well...