What happens when you leave butter in the sun?

Butter is a solid fat made from the milk of cows or other mammals. When butter is exposed to heat, it will begin to melt and become a liquid. If butter is left in the sun for a long period of time, it will eventually become rancid and spoil. This is because the heat causes the fat molecules in the butter to break down, which releases free fatty acids. These free fatty acids can react with oxygen to produce compounds that have an unpleasant odor and taste.

In addition to becoming rancid, butter that is left in the sun can also become contaminated with bacteria. This is because bacteria thrive in warm, moist environments, and butter provides both of these conditions. If you are going to leave butter out of the refrigerator, be sure to keep it in a cool, dry place and use it within a few days.