Although you can find many food dye colours in shops or you can mix your own at home, getting hold of some food dye colours is more challenging. Locating grey food colouring, even when expanding your search from ordinary supermarkets to baking or craft shops, can be difficult. Fortunately, grey food colouring is pretty simple to make, using basic ingredients and common baking utensils.
Measure out your desired amount of white food colouring gel paste. Transfer the white paste to a dark-coloured or stainless-steel mixing bowl. If you use white or light-coloured mixing utensils, they can easily be stained by the black food colouring. If this happens, it may take multiple soaks or washes to fully remove the black food colouring stains.
Add one drop of liquid black food colouring to the white food colouring paste. Be careful to start with just one small drop of black colouring. This will prevent the mixture from becoming too dark too quickly.
Mix the white food colouring paste and the drop of black food colouring together, using a dark-coloured or stainless-steel spoon. Continue mixing until there are no visible black or white streaks and the mixture is combined completely. One drop of black food colouring will most likely turn the mixture a very soft grey.
Add more small drops of black colouring and blend the mixture completely after each drop is added. Continue until you are pleased with the colour.
Lighten the mixture, if it becomes too dark, by adding more white food colouring paste.
If you can't find black food colouring in the shops, you can make it yourself by mixing equal parts of red, blue and yellow food colouring and blending them together carefully. When combined in equal parts, these primary colours make black food colouring.
If you are colouring foods that are already white, there is no need to use white food colouring gel paste. Simply add small amounts of black food colouring until you get the grey that you like.