Is it safe to use cornstarch in canning?
It is not recommended to use cornstarch as a thickener in recipes when that recipe is going to be canned at home. The starch continues to thicken as it cools and is not safe for water bath canning. Cornstarch can be used as a thickener in pie fillings but the pie filling should be used right away or frozen instead of canned. Be sure to try my corn starch free sour cherry pie filling!