You really need to get some soap dyes from a soap supplier. Although food colorings are fd&c they can morph into all kinds of colors in soap. I use blue food coloring for a pretty purple, but that is the only one I have had success with. I only use it because I know how the purple turns out, and I have only found one brand that works for the purple. Soap dyes formulated for cp soap are the most stable, M&P soap dyes are not always stable. I have played around testing different food colors and generally they are not reliable. Stick to soap colorants especially when you're a new soaper, and save the experiments after gaining a more soaping knowledge. Also keep in mind that most lemon fo's fade. Using Lemongrass and Litsea EO's will last much longer. You can also mix a lemon fo with litsea to kick it up and add staying power