Butter is best stored on the refrigerator shelf, not the door, to maintain a consistently cool temperature and prevent it from becoming too soft or melting.
The refrigerator door experiences more temperature fluctuations than the shelves inside. Every time the door is opened, the temperature rises, which can cause butter to soften and even melt slightly. Repeated softening and hardening can affect the butter's texture and flavor over time, making it less desirable for spreading or baking. The refrigerator shelves, especially those in the middle or towards the back, maintain a more stable and cooler temperature, which is ideal for preserving the quality and extending the shelf life of butter. Storing butter in its original packaging or an airtight container on a shelf further protects it from absorbing odors from other foods in the refrigerator.
If you prefer softer butter for spreading, only keep a small portion in a butter dish on the counter for a day or two. This allows you to have spreadable butter readily available without compromising the quality of the rest of your supply stored in the refrigerator.