This is because all water-based materials have been removed and replaced with bake & cake friendly oils; these oils mix through much better than water-based gels (which we know water repels from the oils in your baking).
Colour Flex Red Oil-Based Food Colouring 25ml - Vibrant Concentrated Formula for Chocolate, Buttercream, Cake Batter and More by Sugarflair - Vegan, Bake-Stable
Edible Food Colouring Mill Red Oil Based 100ml Cake Decorating Sugarcraft
Edible Food Colouring Mill Red Oil Based 20ml Cake Decorating Sugarcraft
Colour Mill Oil Based Food Colouring Red - Next Generation Oil Based Food Colouring for Baking, Decorating, Icing and Cooking Food Dye DIY Slime and Crafts - 100 ml
Colour Mill Oil Based Red 20ml - Next Generation Oil Based Food Colouring for Baking, Decorating, Icing and Cooking Food Dye DIY Slime and Crafts 20ml
PME Cake Oil Based Food Colour with Precision Dropper | Red (20ml) | High Pigment Oil-Blend Food Colouring for Buttercream Chocolate Ganache Fondant & Cake Batter