Meringue shells are among the most paradoxical preparations in the pastry chef's repertoire. They're made from eggs, which are highly perishable, but once baked to their signature crisp texture, meringues are so dry that bacteria can't get a foothold in their sweet, airy interior. Unfortunately, this happy state only lasts as long as the meringues remain dry, so proper storage is crucial.
Storing Your Meringue Shells
Meringue shells are usually made by piping sweetened, beaten egg whites from a pastry bag to make the correct shape. Then they're baked in an oven for hours at a very low temperature to dry and crisp the shells without browning them. Once the shells are cool, they should be layered into an airtight container with parchment paper between them. The container can be plastic or metal as long as it's food safe and makes a good, airtight seal. This is especially important in humid climates, where even a slow leak can turn the crisp shells into a gummy mess. The shells may form a tacky surface even when properly stored in a cool, dark place, but this is easily fixed by returning them to a low-temperature oven for 30 to 40 minutes.
- The Professional Pastry Chef; Bo Friberg