Nope, it’s not food coloring.
Food color dye for the application of coloring cement isn’t very effective, because it’s going to require using a lot of dye to achieve a moderately deep color.
However, fabric dye is a better choice for coloring cement because it’s more concentrated so you will need less of it.
There are a few tricks to using fabric dye with concrete, so read on in the tutorial for what you’ll need to look for.
If you are looking for complete, in-depth information on how to color concrete, take a look at the post How to Color Concrete And Cement Crafts.