Some beginner canning mistakes can leave you with wasted food and a huge mess to clean, while others are down right deadly. From broken jars, to poor seals, to botulism. Check out this list so you don’t make one of these costly mistakes.
There a few seriously dangerous beginner canning mistakes to watch out for:
If you make any of these mistakes, you could be risking your health. Botulism is colorless, odorless and tasteless. So while the jars are sealed and everything looks/smells/tastes fine, it’s not. Someone could end up very sick. So don’t make one of these potentially deadly beginner canning mistakes!
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1. Canning Low Acid Foods in a Water Bath Canner
This common beginner canning mistake is a dangerous one. If you make this mistake, you run the risk of botulism.
Low acid foods like meat, seafood, most vegetables, and soups must be canned in a pressure canner. A water bath canner doesn’t reach high enough temperatures to kill off all the organisms that could potentially make you sick.
The pH is too high to kill the organisms that cause botulism. Pressure canners reach much higher temperatures than a water bath canner will, effectively killing . Pressure canning is the only safe way to kill botulism in low acid foods.
Water bath canning works to preserve high-acid foods like most fruits, tomatoes, pickles, jams or jellies, and salsa. Anything with a pH under 4.6 is considered high acid for canning.
High acid foods are too acidic for botulism to grow, so the water bath canner reaches temperatures high enough to kill any other organisms that can make you sick. As long as you follow a tested recipe of course! Bringing me to my next point…
2. Not Following a Tested and Proven Recipe
Creating your own recipes or altering others is another dangerous mistake.
Follow a recipe from a trusted source. This way you know the recipe has been thoroughly tested for safety. They are designed to have the perfect pH to be safely canned.
Changing ingredients can alter the pH, and who knows what the pH is if you make up your own recipe. If it’s too high (over 4.6), botulism can grow.
The processing time is important too. Following a tested recipe ensures you reach high enough temperatures in the center of the jars to kill bacteria and mold spores.
Check out these books for some delicious and reliable recipes:
- Better Homes and Gardens Complete Canning Guide
- The All New Ball Book of Canning and Preserving: Over 350 of the Best Canned, Jammed, Pickled and Preserved Recipes
- The Complete Guide to Pressure Canning: Everything You Need to Know to Can Meats, Vegetables, Meals in a Jar, and More
Save your own creations for the freezer!
3. Not Adjusting for Altitude
Canning recipes are designed for and tested at sea level. If you live at a higher altitude, you need to adjust your processing time. At higher altitudes, it takes longer to reach high enough temperatures to safely kill mold spores and bacteria.
If you have a good canning book, it will have an altitude adjustment chart you can follow. And if you’re not sure what the altitude is where you live, you can look it up here.
Next there are a few mistakes beginners sometimes make with the canning process:
Don’t skip any of these important steps when canning. Make one of these simple but costly mistakes and you might end up with broken glass and a mess to clean up. Or maybe even mold. Not to mention the wasted food, time, and effort you put into those jars!
4. Not Removing Air Bubbles
If you don’t work out all the air bubbles before processing, there could be too much air for the jars to seal properly.
So grab your little air-bubble-remover/head-space-measuring tool and use it! Bringing me to my next beginner canning mistake…
5. Not Measuring Head Space
Flip that little tool around and use it again. If you’re following a recipe from a trusted source, it will give a head space measurement. Follow it!
The head space is designed to leave just enough room for expansion during processing. Too little head space and the contents of your jars can boil over, making a huge mess and preventing the lids from sealing properly.
Too much head space, and there could be too much air left in the jar to get a proper seal. And remember to always remeasure the head space after removing air bubbles. It can change.
6. Not Wiping off the Rims
After filling jars, before putting on the lids and rings, always wipe the rims of the jars. Any food left on the rims can interfere with the seal, leaving you with potentially unsafe food.
Using a funnel helps to keep everything cleaner, but even still, make sure to wipe them down. You don’t want all your hard work to go to waste over such a simple thing!
Then there are a few equipment-related beginner canning mistakes
Make sure you’re always using the proper equipment when canning. You don’t want to end up with wasted food. Or worse, making someone sick.
7. Reusing Single-Use Lids
You might be tempted to reuse lids, but they are single-use. You likely won’t get a good seal with a used lid. On the other hand, rings can safely be used over and over as long as they are rust free and in good condition.
8. Using Any Old Jar
Some people try to reuse glass jars like pickle jars or old mayonnaise jars, but they’re not safe for canning.
They don’t all come in standard sizes and thicknesses. So the lids and rings might not quite fit right, resulting in a poor seal. You also risk jars breaking if they aren’t sturdy enough to withstand the heat.
Finally, there are a few beginner canning mistakes using old, out-dated methods
I’ve seen a few of these floating around the internet lately. These out-dated methods have all been proven unsafe, so please don’t try them! Stick with water bath canning, freezing, or another food preservation method.
9. Oven Canning
I’ve seen some people preserving dry goods like flour or beans lately. This is not safe for two reasons: First, canning jars are not designed for dry heat like that. According to Ball and Kerr canning jars should never be used in the oven. They can explode in your oven, leaving you a dangerous mess to clean up.
Second, the food will not reach high enough temperatures to kill all of the mold and bacteria. The oven just isn’t hot enough. The result – food that could potentially be unsafe to eat. It can actually even make your food go bad faster.
10. Open Kettle Canning
I’ve seen some “canning” recipes that end with pouring hot food into a hot jar, putting on a lid and ring, then flipping the jar. No further processing of any kind. The thought is that as it cools, the lid will seal. And yes, it may be sealed. But you did nothing to kill any potential mold spores or bacteria.
It’s an old-fashioned way of canning things like jams and jellies or pickles. And I guess some people still do it, even though open kettle canning is totally unsafe. So don’t do it!
11. Paraffin Wax Seals
Another old-fashioned way to seal jams and jellies is a paraffin wax seal. You pour thin layers of wax on top of the jam until a 1/2″ thick seal is created. The problem with this is there’s no real way to check the seal. Plus the wax can expand and contract over time, breaking the seal and allowing mold or bacteria to grow.
Wax sealing is not recommended by the National Center for Home Food Preservation because it is so common for these seals to fail and for mold to form.
Now that you’ve learned how to avoid these common beginner canning mistakes, it’s time to get to work!
Go back and check out Canning Basics: Food Preservation Part 2 for a refresher course on everything else you need to know to start water bath canning at home.
Or check out the whole series here: Food Preservation for Begginners