Storage

While meringue batter is never prepared in advance as a mise en place item, generally speaking, the more sugar that has been whipped into the whites, the longer the batter will maintain its volume and stiffness without deflating as it is shaped. French and Japonaise meringues should be piped or spread into the desired shape immediately after whipping, even if the batter cannot be baked right away, as it should be. The meringue will have less stability and will deflate to a greater degree as it is agitated (through spreading or being placed in a piping bag) after sitting for even as short a time as 10 minutes. Italian and, to a lesser degree, Swiss meringues will hold their shapes for much longer. The Italian variety has greater stability because it is partially cooked during preparation. If made properly, it will keep for several hours. However, if too much sugar ends up sticking to the side of the bowl or the whip, the keeping time will decrease.