Here's another perspective that I find quite intriguing: https://www.thekitchn.com/stop-youre-freezing-your-pie-fillings-all-wrong-23048254
I've never done this with berry pies (and generally probably wouldn't do it with any pie for environmental reasons - I just don't like using aluminum foil unless it's absolutely necessary) but I see that this team has found it okay to freeze pie fillings thickened with cornstarch - and suggests adding a bit more on the pie shell itself to soak up extra liquid caused by freezing.
(Going a bit off-piste here) I might add that reading about this technique inspired me to do something similar for apple crisps. I'm feeding only two of us now, so I generally make our fruit crisps in small rectangular Pyrex brand glass containers, so I can easily cover the leftovers with the lid. Inspired by this, I tested lining it with compostable parchment paper and then baking the crisp as usual. I then cooled and froze the crisp, but before it was frozen solid, I gently lifted it out, tightly wrapped it in freezer paper, and froze it. When I wanted to heat it and serve it a few months later, I simple unwrapped it, dropped it (parchment and all) into the same container in which I made it, and baked it at 350 until the fruit started the bubble and the crisp topping was, well, crisp. It worked like a charm! ;o)
Cornstarch doesn't freeze well, so I don't recommend you do that. It could end up spongy, or it could well break on cooking the pie. There is a cornstarch product made specifically for canning purposes, most often sold as Clear Jel, among other names. It is recommended by the FDA and is the starch used by commercial food producers to thicken their products. You can buy it lots of places on the great interwebs, Amazon among them, and sometimes at local farm stores. What you don't use for canning, you can always use in the kitchen the rest of the time just like regular cornstarch. There are two types, cook and no-cook. For the purposes of canning pie filling you want the cook sort. The no cook variety is good for stabilizing whipped cream and thickening up a runny salad dressing, or other cold prep items.
I agree, but would note that after freezing, you'll probably want to cook the filling down a bit, as fruit once frozen and thawed - even when cooked beforehand - always seems to be a more watery than it was before freezing. ;o)
/0cd6170c-ca0c-4a67-8e59-142a18ac0598--2013-0813_small-batch_scour-cherry-filling-071.jpg)
4 Comments
I've never done this with berry pies (and generally probably wouldn't do it with any pie for environmental reasons - I just don't like using aluminum foil unless it's absolutely necessary) but I see that this team has found it okay to freeze pie fillings thickened with cornstarch - and suggests adding a bit more on the pie shell itself to soak up extra liquid caused by freezing.
(Going a bit off-piste here) I might add that reading about this technique inspired me to do something similar for apple crisps. I'm feeding only two of us now, so I generally make our fruit crisps in small rectangular Pyrex brand glass containers, so I can easily cover the leftovers with the lid. Inspired by this, I tested lining it with compostable parchment paper and then baking the crisp as usual. I then cooled and froze the crisp, but before it was frozen solid, I gently lifted it out, tightly wrapped it in freezer paper, and froze it. When I wanted to heat it and serve it a few months later, I simple unwrapped it, dropped it (parchment and all) into the same container in which I made it, and baked it at 350 until the fruit started the bubble and the crisp topping was, well, crisp. It worked like a charm! ;o)