Is it safe to leave butter on the kitchen counter? If so, for how long?

Understanding Butter’s Composition and Shelf Life

Butter is made from churning cream, which separates butterfat from the buttermilk. It typically contains a high amount of fat, usually around 80%, with the remaining components being water and milk proteins. The high-fat content is the primary reason why butter can remain safe to eat when left out of the refrigerator for a period. The lack of moisture in unsalted butter helps to inhibit the growth of bacteria, which thrive in water-rich environments. However, the presence of dairy and the potential for spoilage cannot be entirely ignored.
Factors That Affect Butter’s Perishability
1. The type of butter: Salted butter has a longer counter-life than unsalted due to its salt content, which acts as a preservative.
2. Kitchen temperature: Warmer temperatures can accelerate spoilage, so butter should be kept in a cool, shaded spot.