The color of cheddar cheese can be anywhere from milky white to bright orange, and the flavor is based on the age, type of milk, the cow’s diet, and even the time of year. Cheddar cheese becomes yellow due to the beta-carotene-rich grass that the animal eats which fluctuates throughout the year, causing varying degrees of color for the cheese.

Cheesemakers use a tiny amount of natural annatto concentrate, a seed from the achiote plant, and a common spice in many world cuisines. Cheddars made with the same milk and aged for the same amount of time will taste identical whether they’re colored or not, but the flavor differences depend on how the cheese maker handles the milk.

The microbes that turn milk into cheddar are unique to most cheesemakers and yield particular flavors, whereas young cheddars are mild and become sharper as they age. Regional traditions also have an impact; for example, cheddars in the United States Northeast are sharp, slightly bitter, and minerally, while on the West Coast, they are mild, sweet, and mellow.