Rub a little meringue between finger and thumb. Grainy means the sugar
has not dissolved; perfectly smooth means it has. That single test predicts weeping better
than anything else, and almost every cause below is really a way of failing it.
Those beads of syrup on a baked meringue are undissolved sugar crystals drawing water out
of the foam. No crystals, no weeping.
What makes it fail the test
Sugar added too fast. Tipped in at once, it stays as crystals.
Add it a spoonful at a time with the mixer running, waiting a few seconds between additions.
For a four-white meringue that is several minutes of patience, and it is the single
highest-value change you can make.
Caster sugar not fine enough. Granulated sugar takes far longer to
dissolve than caster. If you only have granulated, blitz it briefly in a grinder first.
Underbeaten whites. Less air means less surface for the sugar to dissolve
into. Beat to stiff peaks: the peak stands upright and the bowl can be turned over
without the meringue moving.
What passes the test and still weeps
Two situations, both about water rather than sugar.
A humid day. Meringue is sugar, and sugar pulls water out of the air.
On a wet day it will weep whatever you do — this one is not a myth.
Too hot an oven. Meringue is dried, not baked. Too much heat cooks the
outside and traps moisture inside, which eventually comes out as syrup. Low oven, long time,
and leave it inside with the door ajar as the oven cools.
The failure that looks the same but is not
Overbeaten whites. The meringue turns grainy and dull and starts separating
in the bowl — and it will fail the finger test for a completely different reason.
The protein has been stretched past what it can hold, and there is no rescue.
Start again.
Two cheap insurance measures
- Wipe the bowl with vinegar or lemon juice before starting, to remove any
trace of fat, which is fatal to a foam. - A teaspoon of cornflour folded in at the end stabilises the meringue and
absorbs stray moisture.
Related:
Why meringue turns yellow ·
Why egg whites will not whip ·
Why sponge cake is dense ·
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