Place whole lemons in freezer bags before storing them in a freezer. When freezing lemons, choose only fresh lemons with no soft spots. Wash the fruit with water, vegetable soap or diluted white vinegar to remove any residual pesticides.
Thaw the lemons at room temperature or dunk them in cool water for 15 minutes. After defrosting, whole lemons turn to mush. To preserve the lemon's pulp, cut it into quarters or slices before placing it in a freezer bag and into the freezer. If only the juice is needed, squeeze lemons into an ice cube tray for freezing. Lemon zest can also be frozen in a freezer bag after grating.
Defrosted whole lemons are perfect for recipes that require only the lemon's juice. Juice frozen in ice cube trays also comes in handy for this purpose. To ease the cooking process, measure the amount of lemon juice in each cube. This is usually between one and two tablespoons, and recording the volume of the cubes prevents wasting more lemon juice than the recipe requires.
Lemons that are quartered or sliced before being frozen can be defrosted and used as garnishes for dinner plates or desserts. They can also be used to flavor teas or alcoholic beverages.