Why is butter naturally yellow instead of white like milk?
Butter's natural golden color comes from beta-carotene, the same pigment that makes carrots orange.
When cows eat fresh grass, they consume beta-carotene, which accumulates in their milk fat. In liquid milk, the pigment is too diluted to see, but churning concentrates the fat into butter, revealing the rich yellow hue. Butter from grain-fed cows is typically much paler because grain contains far less beta-carotene than fresh grass.
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Beta-carotene is a fat-soluble carotenoid and antioxidant that serves as a precursor to vitamin A. When cows graze on pasture, they ingest high levels of this pigment from fresh grass. Because beta-carotene is lipophilic, it dissolves into the fat globules of milk rather than the watery portion. In raw milk, these fat globules are surrounded by thin membranes that reflect light, making the milk appear white to the human eye.Making butter involves mechanical churning, which breaks these protective membranes and allows fat globules to clump together. As the fat concentrates into a solid mass, the beta-carotene becomes dense enough to reflect its characteristic yellow-orange wavelength. This is why pasture-raised butter is significantly more vibrant than butter from cows fed corn or soy-based diets, which naturally contain lower levels of carotenoids.This color became so strongly associated with quality that the U.S. Congress passed the Oleomargarine Act of 1886, partly to prevent margarine manufacturers from adding yellow dye to make vegetable-oil products resemble real, high-fat dairy butter. Today, some commercial butter producers still add natural annatto or extra beta-carotene to maintain consistent color year-round, especially during winter months when cows have less access to fresh pasture.
Verified Fact
FP-0003592 · Feb 18, 2026