Sarah, if you're planning to freeze the pies with partially cooked filling it's important to have a freeze-thaw stable thickener. Cornstarch or flour aren't, and will lose their thickening power after thawing (the starch gels that are formed when cooking are punctured by ice crystals, basically letting the water out of those balloons). If you want to be sure the pies aren't runny when baked, use a modified food starch such as Instant ClearJel, or our Pie Filling Enhancer. They're both freeze-thaw stable. Susan

• Reply