The watery layer between the meringue and the filling (weeping) is usually caused by undercooking. This is where it is important to put your meringue onto hot filling so it can begin cooking right away.
Pies sometimes don’t turn out quite as intended, and cooks both today and a hundred years ago try to figure out why. In a question and answer column in the November, 1921 issue of American Cookery, a reader asked:
Meringue tips for a No Weep Meringue Topping – Best Old Fashioned Southern Cooks
FAQ
How do you fix a watery lemon meringue pie?
How do you keep lemon meringue pie from getting soggy?
Why does my meringue look watery?
What can I do with runny meringue mixture?
Why does my lemon meringue pie get watery?
So why does your lemon meringue pie gets watery, and how to fix it? The reasons for lemon pie getting watery could be not pre-baking the crust, whipping the lemon custard or meringue too much or not enough, filling the crust while it’s hot, not adding enough corn starch, and not letting it cool before serving.
Why is my lemon pie watery?
The reasons for lemon pie getting watery could be not pre-baking the crust, whipping the lemon custard or meringue too much or not enough, filling the crust while it’s hot, not adding enough corn starch, and not letting it cool before serving. You can do a few things to fix it, depending on the reason.
How do you avoid a weeping lemon meringue pie?
To avoid a weeping lemon meringue pie: (1) Spread the meringue on a warm filling to create a good “seal.” We keep the filling warm by pressing plastic wrap against the filling while making the meringue; and (2) When you spread the meringue on top of the filling, ensure that the meringue touches the pie crust the entire way around; no gaps!
What happens if you fill a meringue pie while hot?
You will have a runny lemon meringue pie if you fill the crust while hot. What will happen is that you will top the hot crust and seal the vapor inside. This sealing will create moisture between the crust and the filling, making the filling and meringue slide off your pie.