WHY is butter yellow when milk is white?Butter consists of more fat.
Dairy fat is given its color by carotenoids, the red-yellow pigments, particularly vitamin A. Fat is present in both milk and butter. Still in milk it is in the form of an emulsion, a suspension of droplets the size of 3-4 microns.
Each droplet is surrounded by the thinnest protein-lecithin shell.
Liquids of this structure look whitish because of light scattering on the surface of the droplets, regardless of the color of their contents.
In butter, the proportion of fat is higher, causing many of the emulsion droplets to merge with each other. The light scattered on them is worse, and the natural color of the fat appears stronger. Ghee, which is almost pure milk fat, looks even more yellow.
