Frozen milk often appears yellow because of the separation of fat from the other components during the freezing process. The fat, which contains beta carotenes, is responsible for the yellow hue. This color change is normal and doesn't indicate that the milk has gone bad.
Here are some reasons why frozen milk might turn yellow:
- Fat Separation: When milk freezes, the water molecules form ice crystals, pushing the fat molecules together. This creates a layer of concentrated fat at the top of the container, giving the milk a yellow appearance.
- Beta Carotenes: The fat in milk contains beta carotenes, which are pigments that give carrots their orange color. When the fat is concentrated at the top, the beta carotenes become more visible, resulting in the yellow hue.
- Light Scattering: The formation of ice crystals during freezing can also scatter light, making the milk appear more yellow.
While the color change might be alarming, it's perfectly normal and doesn't affect the safety or taste of the milk. You can shake the container before thawing to mix the fat back in and restore the milk's original color and consistency.
