Are your tomatoes shriveling too quickly? Chef J. Kenji Lopez-Alt offers a trick for keeping them fresh: First, remove all the stem pieces from the top of the tomato, then place it on a baking sheet with the opening facing down - and put it in the refrigerator. • In the video, the chef demonstrates how to do this - and compares the fresh upside-down tomato to the shriveled one that was stored upside down.