Can I use regular food coloring in my airbrush?

What food coloring is best to use when trying to add color to a bark coating?

• I have tried using gel food coloring and it worked perfectly but only once. After that, it thickened the coating making it extremely hard to cover the cake balls. Would a powder coloring be better or is there an exact measurment I can use for the gel colors where it won't thicken up the coating?

• Answer:

  i use paste colors you can buy at Michale's wal-mart's