Last week I made applesauce in my crockpot and discovered a new obession: hot applesauce. I don’t know why it never occured to me before to heat my applesauce in the microwave before consuming, but I’m convinced it’s the ultimate fall snack.
The applesauce was such a hit and canning’s been so much fun that last weekend Brian and I decided to make some applesauce to can. Please note that, prior to this weekend, we’d sucessfully canned green beans, pear ginger preserves, peach butter, summer squash pickles and apple rings. Applesauce is so simple to make, what could go wrong?
We made the sauce, put it in the jars and processed the jars. As soon as I opened the canner to remove the jars to cool, I knew there was a problem. The water didn’t look as clear as it’s supposed to. One by one, we pulled the jars from the water. Immediately upon setting them on the table, they began leaking applesauce. Every single jar.
Obviously, it’s not a matter of a bad seal, because every jar leaked. Futhermore, the applesauce really separated (we left it kind of chunky…because we like it that way).
Despite the fact that I still needed to break the seal to remove the lids, we transferred all the applesauce to plastic containers and put some in the fridge and some in the freezer, because I had serious doubts that the applesauce was going to keep in the leaky jars.
So, friends with canning experience, what did we do wrong? We left plenty of headspace and have never had this problem before. I’d love to actually can some applesauce before the season is over!
Did you make sure the air bubbles were out? You can use a wooden chopstick or plastic knife (no metal!) around the edges of the jars to get them out… there are likely to be more air bubbles when you have chunky sauce, and they can expand during processing = leaking!
What Julie said. Also make sure you had enough head space.
For the record, this is part of a genuine attempt to improve my abysmal keeping-in-touch record.
As it turns out, Georgia Tech acknowledges certain talents of its “rival” school UGA, …most notably its Agricultural programme. UGA was kind enough to offer some lessons on the science behind food processing and food safety, including canning… and I still have some notes and my Google-fu. (What can I say… my life is a string of coincidences.)
Just to share… pressure canning, rather than boiling water canning, is recommended for low-acid foods. This is just related to the viability of germs in low-acid conditions; it would have nothing to do with leaking. Additionally, apples are usually plenty acidic (in the mid 3.0 range; UGA calls “low acid” foods anything above 4.6). Apples will most likely still oxidize, especially the longer it’s stored. With that said, this is fine to consume; just an aesthetic thing. If it’s going to be long term, one might consider a recipe that calls for citric or ascorbic acid, to control the oxidation. Alternatively, use cinnamon so it’ll be tougher to notice. (=p)
– As mentioned by the previous commenters, get the air out prior to figuring the final headroom. Probably wouldn’t hurt to pour in a third at a time, then get the air out after each pour. A non-metallic implement is recommended (probably just to reduce any effects on flavour). Removing excess air will be especially important when the chunks are large-ish. (Smaller particles will “fall” to the bottom, having fit between the crevices, and large objects will settle against each other: making for larger gaps between each object. Air can find its way in those spaces.)
* If the larger chunks can be separated out first, and put in the bottom of the jar prior to adding the sauce-like portion, that should decrease the amount of air.
* If the tools can handle the temperature (and size of the chunks), “piping” it into the jar (like applying frosting to a cake), rather than using a spoon, would decrease the amount of air added just by the transfer method.
* Just on the troubleshooting standpoint, I’ll mention that it may help to let the sauce cool (especially if it was recently bubbling) prior to filling the jars.
– When heated, the water in food will cause it to expand (and release some air). When heated (during processing), the air will expand faster than the food. As the air is forced out, it creates the vacuum seal. Ideally, the headroom is such that there is just enough room for the food and none for air. If the headroom is too little, the food will press on the lid and prevent a good seal. If headroom is too much, then a significant amount of air is still in there; the air compresses, and the vacuum is weak. Care should be taken regarding the type of jar used. (1/2″ headroom in a wide-mouth jar will be a much larger [~30%] volume than a regular jar.)
– Everything in the canning process is related to temperature and pressure. Altitude, headroom and air/water content will tend to contribute to the pressure. Regarding temperature, …sugar, large food pieces, and thickeners will absorb heat more slowly. Also, increased pressure will increase the temperature …between this and the slow heat absorption of large chunks, …the apples may continue to expand, even after they’ve done being heated. The continuing expansion will, of course, contribute to leakage.
– Regarding the separation, it’s purely due to the water-content of the apples, especially large chunks. The more the sauce can be sieved ahead of time, the more base water will be omitted from the final product. [N.B. This is quite literally apple juice and is undoubtedly delicious.] I would recommend that the sauce should be strained, even if pretty lightly, and can have *some* of the juice added back. This is also a good opportunity to get the solid chunks separated; they can be put in the bottom of the jar (to be stirred up when served) so as to reduce the amount of entrained air.
Sorry for the long-windedness. Best of luck!
Wow, Arjun, you win the award for longest comment ever. I’m not sure that’s really the same as keeping in touch though :).
Several thoughts:
1) We used a recipe designed for a boiling water canner which included plenty of lemon juice, so my apple sauce was safe. Thanks for the concern :)
2) I did attempt to get the air bubbles out, though I never thought about only pouring in a 1/3 of the sauce at a time to aid with this. We didn’t let the sauce cool because one of the things about safe boiling water canning is hot-packing the product, which kills even more germs.
Much of that information I’d already discovered from my earlier canning projects, but there were definitely a few good tips in there. I think we’re done canning until the Spring, but I’ll be sure to update the blog world with my progress!
I was so hoping someone had responded with the answer to your problem! We’ve been canning for more than 20 years and just had this happen to us! Since this happened, have you figured out why? I have a LOT more apples that need canning.
Hi Deborah,
I didn’t get the chance to make applesauce this year, but I did notice the following note in my copy of “Food in Jars” that seemed like it might solve the problem: “When the processing time is up, remove the canning pot from the heat and remove the lid. Let the jars sit in the pot for an additional 5 minutes to prevent the applesauce from reacting to the temperature change and bubbling out of the jars.”
Hope that helps! Please let me know if it works!