My pie filling sometimes oozes out of the top of the jar when I remove the jars from the canner. What did I do wrong? With apples plentiful this time of year, many of us plan to capture the flavor of the season by making, and canning, apple pie filling. Many different fruits can be canned into pie filling: apples, blueberries, cherries, peaches and nectarines, and even green tomatoes (see pp. 28-30 of Canning Fruits Safely.)

Many of you have asked, and my own experience tells me, that sometimes, despite our best efforts, the pie filling tends to ooze down the side of the jars after the jars are removed from the canner.  This is disappointing to say the least.

In classes, we have experimented with several different techniques for trying to ensure that this does not happen.  A few tips may make canning pie-filling a success:

• Follow directions carefully for preparing fruit. This including thawing frozen fruit and blanching fresh fruit. One goal of home-canning is to remove air from the jars so that the jars will seal. Raw fruit can have a lot of air in the fruit tissue. Blanching will help remove some of this air prior to the canning process, leaving less air to be removed during canning (sometimes with pie filling in tow!). Blanch fruit in small batches, changing the blanch water frequently. If you use frozen fruit and it’s not yet thawed, the quick cooking process prior to canning may not completely thaw the fruit and could interfere with gel formation prior to canning, leaving the gel to form, and the product to thicken, later in the process.
• Take care to remove air bubbles prior to sealing. As the filling thickens it can trap air bubbles in the jar. Use your bubble freer to remove those trapped bubbles prior to sealing each jar.
• Use 3/4 of the amount of Clearjel recommended in Extension recipes. Extension recipes call for Clearjel as the thickening agent in the manufacture of canned pie filling. Clearjel is a modified corn starch; modified so that it will not break down as the pie filling is cooked in preparation for canning, heated during the canning process, and heated a third time as the pie is baked. Experimentation has shown that using 3/4 of the amount of Clearjel stated in the recipe will produce a very acceptable filling, but one that is a little less thick and therefore less likely to ooze from the jars. So, if the recipe calls for 1-1/2 cups of Clearjel, use only 3/4 of this amount or 1 Cup plus 2 Tablespoons, and so forth. Extension does not recommend the use of regular corn starch or flour for thickening pie filling as these thickeners tend to break down and a poor quality product results.
• Do not attempt to double recipes. Because it can be difficult to stir the Clearjel/fruit mixture as it thickens prior to putting the pie filling in the canning jar, do not double the recipe but make more batches on any given day.
• Leave sufficient headspace. Pie filling recipe recommend canning in quart jars, just enough for one pie! Be sure to leave at least 1″ headspace in each jar, and take care to remove air bubbles prior to applying the lid. Leaving even a bit  more headspace, up to 1-1/4 inch, can help to prevent oozing.
• Keep the product hot and canner ready to go! Take care to avoid delays in canning, but if this happens, product waiting for canning should be kept very hot, about 180°F internal temperature, ideally in something like a Nesco roaster in 1-2″ of very hot water. Jars should be promptly canned in a boiling water canner or steam canner according to recipe instructions.
• Try leaving the jars in the canner for 10 minutes after the end of the timed process, especially if using a boiling water canner. The pressure of the canner water will help to prevent oozing as the jars begin to cool in the canner.  Be sure to remove jars after about 10 minutes and before they cool completely. Do not hold the jars if using a steam canner; simply remove jars at the end of the processing time.

Canning pie filling in quart jars, rather than pint jars, may also help. If you choose to can in pint jars, follow the recipe for canning in quart jars, retaining 1″ headspace, and using the processing time listed for quart jars.  There are times when cooking is like a kitchen experiment. If your pie filling does ooze out the side, the jar lids will be more stuck-on than sealed, so set those jars aside and store them in the refrigerator.  Enjoy within 2 weeks. Your family will be happy to help you eat your ‘mistakes.’  [And remember to remove bands and wash and dry the outside of jars prior to storage.]

Safe (and tasty) preserving! Barb