Help! I've been trying to make a raspberry buttercream that the customer wants tinted purple. I can get the flavour right(with jam or raspberry jello crystals) but as soon as I put the jam and the purple colouring together it goes like a grey purple colour. Any suggestions?? I'm tyring to stay away from the extracts because she thinks it takes "fake".

Have you tried adding blue color instead of purple?

add a tad of pink.

I would try the pink and also try the extract with maybe a little bit of lemon juice or liquid citric acid. The Citric added in small amounts with up the flavor and make the raspberry taste more fresh, just dont add to much because it can be very sour!