Home Canning - an intro
If you have never been exposed to home canning you probably have questions First of all, you might be wondering, “What IS home canning?” Further, you might ask, “Why would someone can food?” or “Is canning your own food safe?” There is a lot to learn and I know you have a lot of questions. Keep reading for answers to those questions and more.
What Is the Definition of Home Canning?
Home canning is a method of food preservation. It is accomplished by packing food into jars and heating the jars to kill dangerous microorganisms that can make people ill and/or cause food to go bad. By heating the jars, enzymes that can cause the food to spoil are inactivated, thus extending the life of the recipe. When jars are processed, the air is forced out creating a vacuum seal. Home canned goods that use a safe and tested recipe are shelf stable and will last a very long time.
Why Do People Can Their Own Food?
People can foods for all different reasons. Some have abundant gardens and want to preserve some of their harvest to extend throughout the year. Others enjoy creating delicious recipes to share with friends.
Preserving meats to be shelf stable ensures that food won’t be lost due to electrical failure, something that cannot be guaranteed with meat stored in a freezer. Perhaps people can because it makes meal prep easy on busy nights. It’s much simpler to pull out a jar of canned soup to doctor up than starting something from scratch. It can be much more cost effective and some people like to know exactly what goes into their food. The reasons to can your own food are numerous.
What Types of Canning Are There?
Safe canning methods include water bath canning (boiling water bath), steam canning, and pressure canning. Water bath and steam canning are only suitable for high acid foods such as pickles, jams, jellies, salsas that include added acid, tomatoes with added acid, and most fruits. Pressure canning should be used when preserving any low acid foods such as vegetables, beans, broths, meats, soups, etc.
What Is the Science Behind Canning Food at Home?
The science of canning your food at home has a lot to do with pH and temperature. Safe canning recipes ensure that food is prepared in a way that kills off any harmful things present in the food. The air around us, the soil where our food is grown, and even the surface of our foods contains microorganisms that can cause food to spoil and also make us sick. One such microorganism is Clostridium botulinum.
C. botulinum can be found in soil, dust and river or sea sediments. The bacteria itself is not harmful to us, however, when it is left in an anaerobic environment (a vacuum) it produces a toxin that can be deadly.
The good thing is that we know how to prevent these toxins from being released into our home canned goods. Unable to live in a high acid environment, C. botulinum cannot survive in things like jams, jellies, pickles, etc. These items must still be processed in a water bath canner, however, to kill off things like yeast that would otherwise cause spoilage.
To prevent the release of toxins in lower acid foods like meats, beans, broths, etc., the C. botulinum must be killed off using temperature. This is why these items MUST be pressure canned. While boiling water does kill off the bacteria itself, it has the ability form hardy spores that can survive the boiling treatment. If left in a vacuum, these spores will release a toxin. A pressure canner ensures that temperatures higher than boiling are achieved, thus killing off any potential bacteria and spores.
Is Canning Your Own Food Safe?
Home canning is very safe if a person uses tested recipes and methods. Safe recipes mean that they have been tested by a trusted source and proven to meet the necessary requirements to kill potential C. botulinum and other food spoiling microorganisms properly. There are definitely some hard, fast safety rules to consider when canning if you want your food to remain safe.
Are There Unsafe Canning Methods?
Yes, absolutely. People often reply, “My grandma did it this way and we are just fine,” when it is pointed out that a certain recipe or method is unsafe. The fact is, we know a lot more about food science than we did 50 years ago. Your grandma and her surrounding community shared methods that worked for them, but we have since learned that there is a better way. I firmly believe in what Maya Angelou said, “Do the best you can until you know better. Then when you know better, do better.”
Some methods unsafe canning methods you might see when browsing Pinterest or going through vintage recipe books, for example, include:
- Oven Canning
- Open Kettle Canning (Inversion Canning)
- Microwave processing
- Micro-Dome Food Preserver
- Pressure Cooker Canning
- Dishwasher Processing
- Solar Canning
- Wax Sealing
If a recipe you’d like to make uses one of these methods, try to look up a tested recipe to use in its place.
What Are the Dangers of Canning Food at Home?
As previously mentioned, the biggest danger to improper canning is botulism. If a person uses untested methods, as noted above, or an untested recipe, there is a higher risk of getting botulism. Botulism is a very serious issue with symptoms such as droopy eyelid, difficulty swallowing, muscle weakness, double vision, and more.
The symptoms all result from muscle paralysis caused by the toxin. If untreated, the disease may progress and symptoms may worsen to cause full paralysis of some muscles, including those used in breathing and those in the arms, legs, and trunk (part of the body from the neck to the pelvis area, also called the torso). In foodborne botulism, symptoms generally begin 18 to 36 hours after eating a contaminated food.
Remember, botulism can be avoided! Always use safe and tested canning recipes and methods. If you or someone you know has symptoms of botulism, immediately contact your doctor or go to the ER.
What Food Can You Safely Can at Home?
The list of items you can safely can in a water bath canner include, but are not limited to:
- Fruits (preserves, jams, and jellies)
- Pickles, Relishes, and Chutneys
- Salsas (with added acid)
- Tomatoes (with added acid)
- Pie Fillings
- Condiments and Sauces
The list of items you can safely can in a pressure canner include, but are not limited to:
- Meat, Poultry, and Seafood
- Broths and Stocks
- Soups
- Vegetables including Potatoes and Beans
What Foods Cannot Safely Be Canned at Home?
The list of items you cannot safely can include, but are not limited to:
- Fats
- Dairy
- Pasta and Noodles
- Nuts
- Purees
- Refried Beans
- Grains
- Thickeners (other than Clear Gel)
- Pickled Eggs
- Squash
- Cabbage
- Broccoli and Cauliflower
- Eggplant
- Artichoke
- Olives
Some of these items cannot be safely canned at home because it is a safety issue, while others have more to do with the texture of the final product.
Can I Can My Own Made Up Recipes?
It is never a good idea to make up and can your own recipes. Always use recipes that have been through the rigors of testing to ensure that your food product is safe. Botulism is undetectable to the human senses, so if you make up and can a recipe you won’t know that it is unsafe until it is too late.
There ARE some guideline recipes available for things, like making jelly, where any juice or fruit may be substituted, or soups where all the ingredients can safely be canned, but each of those still have tested protocols and methods you should follow.
How Do I Know if a Canning Recipe Is Safe?
With the prevalence of the Youtube and Pinterest recipes, and the internet in general, it is easy to find countless untested, unsafe recipes being passed around. How would you know if something is safe? It is always best to look up and follow recipes from known trusted sources. A blogger or Youtuber who is using a tested and safe recipe usually will indicate so and often-times links to the trusted source. Such sources include:
- National Center for Home Food Preservation (NCHFP)
- Ball’s Canning Website
- The Ball Blue Book
- HealthyCanning.com
- Food in Jars
- Bernardin Website
- Mrs. Wages
- Package instructions on pectin or seasoning mixes
- Any of the USDA Extension Offices Websites
What Do I Need to Start Canning?
To get started canning, you need to know what type of canning you will be doing. Essentially, you will need the proper canner, a set of canning tools that include a jar lifter, funnel, lid picker, and head space measure, pots to cook your recipes that require it, utensils including non-reactive spoons, knives, and ladles, jars, lids, and bands, hand towels, a trusted recipe, and ingredients. Extras include labels, fabric and twine to wrap and decorate the lids, and things like that.
Related Post: What You Need to Water Bath Can
Can I Can on My Stove Top?
The question of stovetops and canning comes up often. You may have heard that you cannot can on a glass top stove, for example. The reasons cited for this are threefold. Older canners may have a concave bottom which can cause a suction beneath the canner. If you try to move a hot, heavy canner that is suctioned to the stove it could be a recipe for disaster.
Secondly, a full canner is very heavy. Some glass stove tops simply cannot handle the weight and are in danger of breakage. Lastly, glass top stoves tend to lack consistent heat, cycling on and off, which could mean maintaining a steady boil cannot be guaranteed.
The good news is that this doesn’t necessarily mean you can’t can atop your glass stove top. The danger of a canner suctioning to the stove can be eliminated simply by using a flat bottom canner. It is advised to check with your stovetop manufacturer to find out if your particular appliance can handle the weight. Finally, you can test for yourself whether your unit can maintain a steady boil by bringing to a boil a pot of hot water. Watch as it cycles and take note of whether or not the boil is affected. Use a thermometer to determine whether the temperature drops below 212°. I, myself, have a glass stovetop and have no problem safely canning. If you follow these steps, you can decide whether or not it is feasible for you.
If you find your stovetop is not suitable for canning, don’t dismay, there are alternatives. A single cast-iron or induction burner may be used outside of the stove or you can purchase an electric canner.
What Are the Steps to Canning?
The steps for both water bath and pressure canning are very similar. These include:
- Gathering all of your necessary tools and recipe ingredients
- Prepping your jars, lids, and rings
- Filling your canner and setting to simmer
- Preparing a safe and tested recipe
- Filling warmed jars, removing bubbles, wiping rims, and placing lids and rings
- Filling the canner with prepared jars and placing the lid on top
- Processing according to safe and tested method
- Allowing jars to rest in the canner
- Removing and allowing them to cool, undisturbed for 12-24 hours
- Checking seals and treating unsealed jars as opened
- Cleaning and storing jars
Of course, these are just an outline of the process. Visit the related post linked below for a more detailed, step-by-step walk-through.
How Do You Store Home Canned Foods?
When it comes to storing home canned foods, there are a few things to remember. First, consider the environment. Temperature and exposure to light are going to have an effect on the longevity and appearance of your preserves. Secondly, the manner in which you store your jars is important in maintaining the safety of your food.
Preparing Jars for Storage
After processing your jars, waiting 12-24 hours, and checking seals, always remove the rings and clean the jars in warm soapy water. Siphoning can sometimes occur during the canning process, which means some of your recipe may have seeped out beneath the lid and onto the rim of the jar. If you do not clean it, it can attract bugs or spoil. Washed and dried jars should be labeled and stored in a cool, dark, clean place with little humidity. Ideal temperature would be around 70 °F, but below 85 ° is deemed safe. Do not store in an area that freezes or is near pipes, in an unused attic, direct sunlight, or any other location where the temperature fluctuates.
Should I Store My Jars With or Without Rings?
Jars can be stored with or without rings, but it is highly suggested to leave the rings off. Leaving rings on can create a false seal on spoiled foods. If a ring is left off and food spoils, it will be easy to detect as the lid will no longer be attached to the jar. Leaving the ring on could cause the lid to reattach giving the impression that the food inside is fine, when it is not.
Is It Safe to Stack Jars?
Stacking jars can be done, but manufacturers suggest no more than two jars high. My personal preference is not to stack, but if you cannot avoid it, best practices for stacking would be to store jars in the manufacturing box atop the first row of jars. This prevents a protective layer so as not to disturb the seals on the bottom row.
Rotate Your Stock
Be sure to rotate older stock to the front as you continue to add newly canned food to your pantry. Older jars should be consumed first to ensure nothing is wasted. Food quality will degrade over time, so “first in, first out” helps to consume things before they are no longer enjoyable.
How Long Are Home Canned Foods Good For?
The common advice given about home canned food is that unopened, safely canned foods are good for one year. It is often suggested to only can what your family would eat in that one year. However, home canned foods may safely be consumed for many years after process date. The issue of canned food longevity is rarely about safety but more about the enjoyability of the product.
After time, the texture of the food may become softer and less desirable and the food loses nutritious value. Low acid foods will last longer than higher acid foods, so keep an eye on the jams, jellies, and fruits. Safely canned food can safely be consumed years after the preservation date, but it won’t be as enjoyable as a more recently preserved jar.
How Do You Know When Canned Food Has Gone Bad?
Check the Lid
It is typically pretty easy to tell if a home canned jar of food has gone bad. A simple visual examination of your canned goods is the first step. A failed seal is the first thing you will usually notice. When something is sealed correctly, the top of the lid flat will be depressed and you will not notice any flexing when you press the center of the lid.
If at any time any of your jars show a flexible lid, toss the contents of the jar. If the lid is no longer attached at all, throw the contents in the trash. Additionally, if you have stored your jars with the rings on and you have a bulging lid, throw the contents away.
Closely Examine the Contents
Before opening, take a look at the food inside. If the contents are bubbly, it is unsafe to consume. This means there is contamination of the food and should not be eaten. Should your jar spurt food out when you open it, it is best not to consume the product. This indicates the food inside was under pressure, again a sign of spoilage. There should be no scum on the top layer of the food and there should be no unnatural colors. Lastly, once you open the jar, if it smells off, toss it. The mantra safe canners live by is, “When in doubt, throw it out.” NEVER taste a food you are unsure of. It is never advised to take a chance if you are unsure of the safety of your jar.
Finally, these safety checks are in regard to food spoilage. Remember, botulism is odorless and shows no visible indication of its presence, which is why it is always important to make sure you use safe canning recipes and processes.
Safely Discard Spoiled Food
When discarding spoiled food, be sure to keep it away from friends, family, and any animals that might be able to find it. Should your family pet get into the garbage it may get sick from ingesting the discarded food. Wash the jars after dumping the food, and sterilize them for future use by placing in a pot, covering with water, and boiling for 30 minutes.
Tips for Getting the Most Out of Your Canning
Have Everything Ready Before You Begin
Canning is a very precise operation. Having all of the necessary tools and recipe ingredients ensures that you can move through the recipe and process without delay.
Know What You Can Prep Beforehand
While most recipes can and should be executed all at once, some foods may be prepped a day ahead to split up the workload. For example, if you are processing a large amount of green beans, on day one you may wash, sort, and snap the ends off and on day two you would only need to fill your jars and process. Doing all of this in one day can be exhausting.
Use Only Tested Recipes, Do Not Improvise
Clearly you can see by the number of times it’s been mentioned, it is super important to only use safe, tested recipes. Do not think that you can simply can up your homemade sauce and that it will be safe. Your family’s health and wellness should never be gambled with simply because you don’t want to follow instructions.
Use the Correct Canner and Process
In the same vein as above, be certain about the method of canning that is appropriate for your recipe. Do not try to water bath low acid foods at a longer time thinking that it is a substitution for pressure canning. Additionally, NEVER use a pressure COOKER in place of a pressure CANNER.
Know What Types of Ingredients You Need
Certain ingredients have variations available for which a specific type is necessary to can safely. For example, when canning avoid using table salt as the iodine causes cloudiness in your jars. Another example is lemon juice.
If a canning recipe calls for lemon juice, unless it clearly states to use fresh squeezed, bottled lemon juice should be used to ensure consistent acidity. Vinegar must always be at least 5% acid.
Know When it is Necessary to Sterilize Your Jars
It is not always necessary to sterilize your jars. When water bath canning, sterilizing is only necessary if your processing time is less than 10 minutes. Pressure canning does not require sterilization of jars.
Warm Your Jars
Warming your jars before filling and processing ensure that they do not break from thermal shock. If your jars are not warmed and you fill with boiled water or place them into the simmering canner, the drastic temperature change can cause them to crack.
Buy Trusted Lids and Jars
During the early stages of Covid and lockdowns, we noticed a shortage of trusted lids and jars. Because of this people were forced to buy off brand lids that often came from overseas. There is no quality control and a lot of people were disappointed when the cheap lids buckled or failed. Always purchase lids from a trusted brand and distributor.
Use a Checklist So You Don't Miss a Step
Keep track of your progress through a recipe so you don’t miss any important steps. One missed step could mean you have to reprocess the entire batch and you’ve wasted a lot of time. If you find out after 24 hours that you missed a step, you’ve just wasted an entire batch of food.
Measure Headspace
Always measure your headspace when you fill your jars to the correct number noted in your recipe. Incorrect headspace can cause food to spoil and the jars to be unsafe.
Remove Bubbles
Use either a plastic or wooden tool to remove any bubbles from the jar before adding the lids. Re-measure for headspace and fill to the correct measure if necessary.
Wipe Rims
Before putting the lids on your jars, be sure to wipe the rims to remove any remnants of food. If there is anything between the jar and the lid, your lids could fail and you would have to either reprocess or store your jar as an opened one.
Leave the Jars in the Canner After Processing for the Allotted Time
Whether pressure canning or using a water bath canner, most recipes will call for a waiting period at the end of processing before removing the jars. Do not skip this step. This helps to slowly bring the temperature of the jars down so that siphoning is prevented. If a hot jar is immediately removed from the canner and placed on the counter to cool, the temperature change can be too drastic too quickly.
Do Not Leave The Jars in the Canner Too Long
Conversely, do not leave your jars in longer than the recipe calls for. Doing so can cause what is referred to as “flat sour”.
Do Not Tip or Tilt Your Jars When Removing From the Canner
When removing your jars from the canner, be careful not to tip them, but rather remove them straight up. Any water that is left on the lids will quickly evaporate as they sit on the counter. Tipping the jar to remove the water from the lids could cause the liquid inside to get under the lid causing the seal to fail.
Place Jars on a Barrier to Cool
Just like putting hot water into a cold jar can cause thermal shock breakage, putting your hot jars directly onto a cold countertop can do the same thing. Always place hot, processed jars on a barrier on the countertop and out of any possible drafts to allow the temperature to lower at a slow pace.
Check Seals at 12 Hours
Freshly processed jars should be left undisturbed for 12-24 hours. Do not depress the lids yourself while they are cooling off. In fact, don’t touch them at all. After 12 hours, it is safe to check the seal by depressing the lid. If the lid flexes, either re-process the jar or place in the fridge or freezer and treat it as an opened jar.
Label and Store Correctly, Rotating Stock
Always label your jar with the contents and the date processed. Read above about how long home canned goods are ‘good’ for. Rotate your canned goods by placing newly processed jars behind old jars. This ensure that older processed jars are eaten first and nothing goes to waste.
When in Doubt, Throw it Out!
Finally, and probably most importantly, NEVER ever consumer or serve food you are unsure of. If you receive canned goods from a friend or family member and you aren’t sure of the safety, you have two options; ask them how they made and processed it, or toss it and never tell them. If you discover that you have processed 9 quarts of tomatoes improperly, don’t just chance it because you don’t want to waste it. Throw it away and take it as a lesson learned.
Final Thoughts on Home Canning
If you have never canned before and you came to this post looking for information, you’re probably feeling a bit overwhelmed. I know it can feel very daunting and maybe even scary because of the emphasis on safety.
While obviously safety is very important, I want to assure you that you can do this! Take a look around the blog, read the posts, visit some of the beginner canner posts and jump in. As long as you are following trusted recipes you will be fine!
Some people find sticking with water bath canning makes them the most comfortable as the threat of botulism is greatly reduced. Start there. Try your hand at making pickles or jam. Make several batches of canned goods until you get comfortable with the whole process and all of the steps. Eventually you may feel ready to tackle pressure canning. When you are, this blog is here to walk you through it. Take a deep breath, grab your tools, and let’s get started!
2 thoughts on “Home Canning – An Introduction to the Basics”
One of my favorite parts is after the jars have set, taking the rings off and washing the jars off with soapy water. That’s when you can really see the beauty of your home canned jars. It really gives me a sense of pride when I see what what I have put up.
I love that part too! It’s so nice to see a fully stocked pantry that you’ve done all yourself.