- Arrowroot or cornstarch
Best Option: Replace the tapioca with an equal amount of arrowroot starch. This will thicken up the filling just as well as the tapioca, and give the fruit a beautiful glossy sheen.
In a Pinch: Replace the tapioca with an equal amount of cornstarch. Your pie filling won't come out quite as thick and glossy as it would with tapioca, but it'll still taste great. If you plan to freeze your pie, this isn't a good substitute to use; pie filling made with cornstarch gets spongy when it's frozen.
Note: These substitutes are intended to replace the tapioca in pie fillings, cobblers and similar dishes. Do not use them as a substitute for the tapioca in tapioca pudding recipes.