7 Controversial Canning Mistakes That Can Cost You Your Health

There’s common canning mistakes…and then there’s canning mistakes that can cost you your health.

Every year, I see the same articles floating around the internet and getting shared on Facebook. And I worry for the unsuspecting people who will follow this bad advice, and make all sorts of canning mistakes that might lead them to a hospital visit (and a big ol’ bill).

Canning vegetables should be a fun and easy process, and it is, when you follow established directions that are safe and have been studied.

In this article, we’ll debunk a lot of the canning myths I see floating around on the internet so you can feel confident canning your harvest.


One common response to debunked canning mistakes usually is something like “well, my grandmother did it and nobody died, so it must be okay.”

Yes, reported cases of poisonings from home canned goods are relatively rare. But that’s because a majority of people follow canning recipes outlined by research institutes such as the National Center for Home Food Preservation.

This center has studied many food preservation methods, which have helped to establish which home canning recipes and practices are safe – and which are just canning mistakes you want to avoid.

Here’s 7 canning mistakes you might see on Facebook. You should avoid these myths so you don’t get sick.

Mistake #1: Oven canning is safe

Oven canning, which involves placing filled jars in a hot oven then allowing the heat to seal the jars, is one common canning tip that’s totally a safety don’t.

The simple reason is the contents of your jars may not get hot enough to actually kill all the bacteria and mold spores in your food, which then have a likelihood of growing inside your jars.

While both water bath and pressure canning rely on water to conduct heat to kill bacteria, mold, etc. that might spoil food, the oven canning method involves only dry heat. Because dry heat does not raise temperatures as consistently as water, there’s no telling what the temperature inside the jar has reached.

Even if you leave your food in the oven for the same amount of time you would if you were water bath canning, the inside of your canning jar might not get as hot as it needs to be to properly kill all the bacteria crawling inside. It’s one of the most common mistakes we see!

Mistake #2: Flipping a hot jar upside down seals it well enough, and waterbath or pressure canning isn’t necessary.

A few articles on the internet offer the advice that that after filling a hot canning jar, it’s perfectly safe to flip it upside down to get the lid to seal. While your lid might seal, it’s potentially too weak to make a really sticky seal, and you might find in a few months that your jars are no longer sealed at all (and have a big green moldy mess).

Additionally, one of the most common mistakes with this method is that your food, which you just ladled into the jar, also probably didn’t reach a high enough temperature to kill off any nasties lurking around to spoil your food.

According to science, the biggest reason that water bath and pressure canning are safe is because they raise the internal temperature of the food to a high enough degree that a most of the bacteria and mold spores are killed.

If you rely on flipping the jar to create a seal, you’re making more than just a few mistakes by skipping an important step.

Mistake #3: Paraffin wax is an excellent sealer

Using paraffin to seal food is another common mistakes we see when it comes to canning. Using paraffin in canning to preserve food involves placing thin layers of wax over your jar until there’s about a half inch of wax that seals the opening.

Back in the day, canning with paraffin wax was considered safe, but the research shows that the bacteria and spores just aren’t sufficiently destroyed. There’s also no way to determine whether the jar is actually sealed well enough.  Stick with new mason jar tops!

Mistake #4: Inventing your own recipes is okay

While I’m always tempted to create my own salsa recipes, the truth is that inventing your own canning recipes isn’t a good idea, and so it’s 4th on our list of common canning mistakes. The canning recipes you see in the Ball Blue Book Guide To Preserving and on the National Center for Home Food Preservation website have been rigorously tested for safety.

If you create your own canning recipe, the amount of acid needed to safely preserve food might be off (a pH of 4.6 or lower is advised), or the temperature might not get high enough to adequately destroy bacteria and mold spores present. If you want to make up your own canning recipes, you can always freeze it.

Mistake #5: If it’s canned at the store, then it’s ok to can it at home

This is one of the biggest common canning mistakes I see. Here’s why: Commercial manufacturers spend a lot of money researching canning and safe storage techniques. They also can heat their canning recipes to a higher temperature than we’re able to using our own equipment. While they have methods and data to safely preserve certain foods, we do not, and we can’t repeat these techniques at home.

Mistake #6 It’s not necessary to boil lids before canning

On the contrary, it’s very important to boil mason jar lids before using them to preserve fruits and veggies. While sometimes you’ll read that the lids will get sterilized during canning anyway, simmering the lids is meant to heat the rubbery part to ensure a proper seal. The last thing you want is to make mistakes that cause a poor or faulty seal to destroy all your hard work.

Mistake #7: Canning butter is safe

I frequently see recipes and articles that recommend preserving butter by pouring hot, melted butter into heated jars, then sealing the product by flipping it. In fact, it’s one of the most common mistakes I see shared on Facebook, and a hotly debated topic.

While it seems logical that dairy can be preserved in jars, at this time, there are no safe canning recipes to preserve butter out there. Butter is a low-acid product, meaning botulism spores have a better environment to grow.

Fats like butter can also protect bacteria from heat during canning, so for now, preserve your butter at home by freezing it. Kept at room temperature, your canned butter will quickly spoil.

Canning and preserving fruit & vegetables is safe....unless you make one of these common canning mistakes. Here's how to avoid them & stay healthy!

Canning Vegetables Step-By-Step Instructions

This year we’ve been lucky enough to have bumper tomato and squash crops – which means it’s time to get canning vegetables!


I’m a huge salsa fan. Like yogurt and mozzarella, salsa is one of those things I can always eat. So I make sure to can a TON of it to keep me going throughout the winter.


When you can anything, salsa included, you need to make sure you do it right. The last thing you want is to ruin the harvest you worked so hard to preserve or worse – get sick.


How to get started canning vegetables:

Step 1: Observe safety rules such as making sure you process your canned vegetables according to standard safety practices.

Step 2: Have necessary tools such as mason jars, lids, rings, and a water bath or pressure canner on hand.

Step 3: Decide whether you’ll use a water bath canner or pressure canner, and familiarize yourself with your unit’s instructions for use.

Step 4: Clean and sterilize your jars by washing them in warm, soapy water.

Step 5: Pack your jars according to the recipe you’re using.

Step 6: Process your jars of vegetables.

Step 7: Store your jars in a cool location away from sunlight. 


But here’s the deal:

Canning is one of those things you can learn in an apartment or on a 100 acre homestead – which means you can start building your homestead anywhere.


If you live in an apartment or your HOA won’t let you grow food, just head down to a farmers market and buy as much of the freshest in-season produce you can afford. 


You can also can most meats and fish – so if you buy your meat in bulk, have a lot of luck fishing, or just find a great deal at a store you don’t wan’t to pass up, you can preserve it for later.


What do I really love about canning?


During the coldest days of winter, you can still have a taste of summer. 

Confused about canning? It's easy! This article covers the basics of canning, including how to do it, what to buy, and where to buy it! From FrugalChicken

Canning basics


Why bother?

While this is fairly intuitive, the point of canning anything, salsa included, is to preserve the freshest foods for times when they might not be so abundant.


That being said, the first step to learning to can salsa is to choose only use the freshest food, and make sure your ingredients are free of mold, soft spots, or any discoloration. In this case, the quality of your salsa ingredients counts!


canning tomato basics


Safety first

The number one rule of thumb is to not make certain canning mistakes, which means you want to make sure you remove oxygen, destroy enzymes and prevent the growth of undesirable bacteria, yeasts, and molds that threaten to destroy your harvest and render the food unsafe.


You want to use a method to can your salsa so that the glass jars and lids form a good vacuum over your harvest so that liquid stays in, while air and microorganisms stay out of the jar so they don’t destroy it.


Necessary tools for canning vegetables

Luckily, to can your harvest, you’ll only need a few inexpensive tools.


First, you’ll need mason jars, lids, and rings, which can be purchased online or at any grocery store.


The mason jars really are a great investment because they can be used for many, many years.


When we first moved to our homestead, the previous family had a huge collection of old mason jars they passed down to us – score!


Even though they were decades old, they were still very usable.


You’ll also need a few specialized tools, such as:

  • A plastic or stainless steel funnel
  • A stainless steel ladle
  • A canning jar lifter with rubber grips
  • A good pair of kitchen tongs
  • Magnetic lid lifter and bubble remover
  • Pressure canner


You can purchase these items individually, but your best bet is to buy a kit (you will have to purchase the pressure canner separately) – that way you’re getting everything at once, and when you start to can, you won’t have missed anything.


Using a pressure canner

Pressure canners used to get a bad rap because old, old models had a possibility of exploding. (pressure and all…)


But today’s models are more advanced and a perfectly safe. If you can find a used one, go for it.


Buying new works as well (full disclosure: I purchased mine new because I wanted to make sure it would work.) 


Follow the directions that come with your pressure canner to use it properly.


Clean and Sterilize Your Jars

Be sure to have all your tools on hand before starting, and decide what size mason jars you will use. They are available in ½ pint, pint, 1½ pint, quart, and ½ gallon sizes.


Before you use your mason jars, wash them in hot, soapy water or run them through the dishwasher.  Just be sure they’re free of soap when they’re clean so the flavor of your food doesn’t get ruined.


You can also soak mason jars for several hours in a solution containing 1 cup of vinegar per gallon of water.


Sterilizing your jars

You will need to sterilize your jars for anything you want to preserve that will be processed less than 10 minutes.


Before sterilizing your jars, prepare the food you want to can. You will place your food into the jars immediately after they’re sterilized.


To sterilize your jars, place them right side up on the rack in pot of boiling water. The rule of thumb is to fill the pot and jars with hot water to 1 inch above the tops of the jars.


Boil 10 minutes at altitudes of less than 1,000 ft.( At higher elevations, you should boil for 1 additional minute for each additional 1,000 ft.)


Using your canning jar lifter, remove your sterilized jars and fill them with the food you want to preserve.


Remove your lids and rings from the water using the magnetic jar lifter


For jams and jellies, or anything with liquid, it’s a good idea to use your funnel.


Top with the lids, making sure to tighten the screw bands.


Processing your jars 

The best book on the market for processing times is the Ball Blue Book.


Every homestead that wants to can their harvest should have a copy on hand. For the value, the price is negligible.


Once you’re done processing your jars, don’t retighten the lids. You’ll know they’re properly sealed when you hear a “ping” after you process the jars and the tops are indented.


Store your jars in a cool location away from sunlight.

It’s necessary to store them below 95°F, and it’s optimal to keep the temperature between 50° to 70°F to maintain the quality of your canned produce.


I’d love to hear from you!


What will you try canning first? Leave a comment below, or email me!


Like this article? Try these recipes!

Classic Strawberry Jam

Peaches & Basil Jam

Blackberry Chia Seed Jam