When the food colouring was first dripped onto the milk, it floated as a dot of colour.
Because the food colouring is less dense than the milk surrounding it, it floats in the position where it was applied.
The coloured milk is repelled to the edge of the bowl when the first of the soap was dropped.
This is what too much soap looks like. We found out that more soap will create bubbles which will continuously feed in colour. However, without bubbles, the milk will still swirl and mix into each other.
If the soap is applied close to the food dye, it pushes the milk into the area of colour, creating a different shape.