I’m a big fan of doing things at home, making food for yourself, and generally believe homemade is best. You can read my manifesto for more on the purpose behind this blog and truly, I love helping my Wildflower readers learn how to make things for themselves. There’s a few situations where you cannot make something at home and one of those is canned pumpkin puree.
This subject undoubtedly will bring about cries from readers who will say truthfully that they themselves, their mother, grandmother, and great grandmother have been canning pumpkin puree for years and no one has ever gotten sick.
To them I will say that I am truly happy that they’ve never gotten botulism. That would be a real bummer to have diarrhea for a week, or worse, if you were elderly or had a compromised immune system.
One of my favorite college professors specialized in food, culture, and literature. She had red hair and wore fabulous clothing and taught poetry, among other things. She taught me a lot about how strongly people feel about their food and the love that goes into preparing it. I showed up to every single one of her classes at 8 am on Friday mornings in Taylor Hall of Chico State, even though Thursday nights were a very fun night indeed and I would have much rather slept in because she was such a great teacher. She shared example after example of how we eat what we eat, because of our mothers, because of our geography, and because of our husbands. It all made perfect sense to me, and her early morning lessons really ring true now that I’m blogging about canning.
I had a follower on social media recently reference the 1973 edition of the Better Homes and Gardens Canning Cookbook when she stated that she was following the directions therein to can pumpkin puree. I’m sure that book had great directions for doing so…44 years ago. I too love reading old cookbooks for inspiration and using recipes that my great grandma used- those old recipes make me feel genuinely connected to the women in my family and the recipes are usually dang good!
But here’s the problem. Canning science has improved in the last 44 years, and the latest recommendations by the USDA are that you CANNOT can pumpkin puree.
I could not, in good conscience, suggest to any reader, that they can pumpkin puree based on that science.
Pumpkin is a low acid vegetable. It is also very dense. Even in a pressure canner, which gets over 220 degrees, it is too dense for the heat to reliably penetrate the puree to kill any potential botulism spores.
Don’t worry, new canners; there are VERY FEW items that you cannot preserve in a home canning setup and this is one of them. Truly, very few. And, just like when you bake bread, you don’t have to understand why or how the bread rises. You DO have to follow the directions in order for it to work. Canning is the same. You just have to follow the directions.
All foods have an acid value, which I explain in detail in this blog post, but you can download this free acid & canning chart which lists the pH of all the foods you might can for reference. It will show you that lemons have an acid level of a 2 (high acid!) and tangerines are significantly, and somewhat surprisingly less acid 4. It will list all the low acid veggies, like pumpkin too. Download it here!
You may, according to the USDA, can in a pressure canner cubed pumpkin, but I would consider this to be an intermediate canning activity. No freshmen allowed 😉
Cubed is required because a trusted recipe source (the USDA for example) TESTED the size of the cubes (1 inch by 1 inch) and measured the heat inside those little cubes to be sure that it was hot enough inside to kill the spoilers that would make you sick.
It is for this reason that you cannot ever can spaghetti squash at all– it won’t hold a cube shape and becomes a mushy mass that the heat, again, can’t reliably penetrate. And, doesn’t that sound super unappetizing? I love canning, but canning is NOT the only way to preserve food and given that squash comes naturally in a shell that protects it quite well from the elements, I’d suggest storing in a cellar far before tackling preserving it in jars.
Cubed winter squash must be peeled first, which seems like a colossal chore to me personally, but it can be done.
So, what should you do if pumpkin is your favorite fall flavor and you want to preserve it?
It can be frozen, and I’d recommend these wide mouth pint jars for freezing.
Those jars have a freezer safe line right on them, are easy to clean by hand or in the dishwasher, and are my favorite for canning.
You can read this page on the USDA site for more detailed, and tested by science specifics on exactly what you can and cannot do with pumpkin.
To be clear, “puree” also refers to pumpkin butter, pumpkin pie filling, mash, mush, or anything that’s not a 1×1 inch chunk. No pumpkin baby food, no smooth pumpkin of any kind. No can do- pun definitely intended 😉
Canning pumpkin is not safe.
If this post was interesting to you, I’d highly recommend you download the Acid & Canning Chart– it lists the pH values for all the foods you might consider putting into jars, include cocoa, persimmons, tuna, and more. I’ll let you download it to see where those yummy items fall on the scale 🙂
If you are feeling too beginner for an acid chart, I have a completely free Canning Basics Course that I’d love you to join. Teaching beginners is my absolute favorite and you’ll learn how to get started making jam, pickles, applesauce and more. It’s easy, fun and free! Join here!Enroll Now!