My 1 year old wont eat?

My daughter used to eat a lot of different foods. Over the last few weeks she has started refusing food. She wont eat anything I make her and she also turns her nose up at Jar food. The only thing she wants to eat is yoghurt, biscuits & crips. She used to love toast and cheese but now she just picks it up, pulls a face and drops it! I can make chicken dinners, stews etc and she is not interested at all. Any one have any advice?