I mada a Barney cake for my niece when she turned 2 and it called for alot of purple.. I do not know why or is it just me that all the vibrant colors, like purple, black, red, green they have a bitter taste to them.
Is their other ways to get the colors without the bitter taste? I used butter cream icing, I also want to know what is diffrence between butter cream and royal does it taste diffrent? I prefer whipped becuase I dont like the Sugary taste.
I am a new beginner at this I basically have taught myself all that I know.
I am going to see in taking classes so that I can learn other things and learn how to make flowers.

I am fairly new at this but I do know that Royal icing is generally not used for icing a cake. It gets hard when it dries (like those little decoration thingies you can buy in the store I think). That is why it is used for a lot of flowers and they will dry.

As far as colorings, what type of colorings are you using? Black and red are hard to get vibrant. I havent had any problems getting purple and green tho. The few tricks I know for black is to start with chocolate frosting, and for red to start from darker pink. Also which brand are you using? I also know they make dry colors (ie powder) but I have not worked with those and do not know if they will solve your dilemma.) Maybe someone with more experience has some more advice.

I am fairly new at this to.
I live in Cincinnati Oh and i got my coloring gels from Sugar Craft they are Wiltons brand.
The purple that I used was also made buy Wiltons and it turned to be very bitter tasting. I have never used any other colors but Black (I mixed a ton of colors togeher to get it) and purple and green.