Book 9, Question 79
Why Do Leafy Greens Wilt in the Fridge?
Leafy greens wilt in the fridge because they lose water! Their cells are like tiny balloons filled with water, and the water keeps leaves crisp. When the water leaks out into dry air, the leaves go floppy.
More fun facts
- Leafy vegetables start to wilt after losing only about 3 to 5 percent of their water, while nectarines do not shrivel until they lose about 19 percent.
- Leaves have a lot of surface for their size, so spinach or lettuce loses water much faster than the same weight of apples or potatoes.
- Produce loses water faster when the air is warmer and when the air is drier.
- Storing fruits and vegetables uncovered in a home refrigerator causes them to lose a lot of water.
- In a home fridge, temperature swings make water vapor in the air turn to frost or droplets on the cold cooling coil, which leaves the air drier.
- The cooling coils in home refrigerators are often about 6°C colder than the temperature the fridge is set to.
- Grocery stores sometimes mist leafy vegetables in their displays to keep them from losing water.
Sources: postharvest.org
Questions kids ask
How can I keep greens crisp longer?
Keep them covered in a bag or container in the fridge, so the dry fridge air cannot pull water out of the leaves as quickly.