Lemons shrivel in the fridge due to moisture loss. To prevent this, store them in an airtight container or a sealed plastic bag.
Lemons, like other citrus fruits, are susceptible to dehydration when stored in the refrigerator. The cold, dry environment of a fridge draws moisture out of the lemon's skin, causing it to become wrinkled, hard, and less juicy. This happens because the lemon's peel is porous, allowing water to evaporate over time. The rate of moisture loss is accelerated in the low-humidity conditions typically found inside a refrigerator. By creating a barrier against the dry air, you can significantly slow down this process and keep your lemons fresh for a much longer period. Storing lemons in an airtight container or a sealed plastic bag helps maintain a higher humidity level around the fruit, preventing moisture from escaping.
For even longer storage, consider placing a slightly damp paper towel inside the airtight container or bag with the lemons. This will further increase the humidity and help keep the lemons plump and juicy for several weeks.