High temperatures soften the skin and the juice sacs inside the lemon so you can more easily squeeze out the liquid, says Katzie Guy-Hamilton, director of food and beverage for Equinox in New York City and author of Clean Enough.
Vitamin C, however, is heat-sensitive. If you warm a lemon up for 20 seconds, you may also kill 10 percent of its nutrients, she notes. Plus, the citrus will burst if left in the microwave too long.
The bottom line:
Keep lemons at room temperature and roll them on the counter for 10 seconds while applying pressure with your palm and body weight, Guy-Hamilton suggests. This makes the skin more pliable and breaks up the membranes, releasing more juice without vitamin loss.