coloring
colouring
food coloring
food colouring
food color
food colour

So the fake blood is made of corn syrup and food color.

Easter eggs can also be dyed with natural food colors.

At first, I tried painting food color directly onto the cookies, but that just made a mess.

Dissolve a little bit of red food color in some water.

If you'd like the colors to be darker or more intense, add more food color and repeat.

Furthermore the "oil" was in fact cold tea with food colour.

Add some food colors to water and partially freeze the solution.

Blue food colour was used to give an ocean look to the water.

Certified food colors generally do not add undesirable flavors to foods.

Most other countries have their own regulations and list of food colors which can be used in various applications, including maximum daily intake limits.