The Basics of Water Bath Canning

The summer home stretch is here and I’m inviting you to savor every moment by showing you how to host your very own canning party.

Ready to be stored away, these jars of jam and salsa celebrate all the beautiful summer produce (Blueberry Ginger Jam, Salsa Verde & Strawberry Ginger Jam).

I’m going to start off this post with some clear cut honesty: I’m NOT a canning expert. 

In fact, I only began canning foods a few summers ago. Thanks to an abundance of tomatillos from our CSA and a growing interest in eating more seasonally even in the long Northeastern winter, I started by making a few jars of salsa verde. 

This isn’t a post to get you to become an expert canner (but cool if you’d like that!) but rather, to generate an interest in this long standing traditional way of eating that has so many benefits.

What is Canning?

So, let’s start with the real basics….what exactly is canning?

At its most simplest definition, canning is simply another form of food preservation that allows cooked food to be preserved in sealed cans or jars that are sterilized by heat.

There are two types of canning: water bath canning and pressure canning. I won’t be talking much about pressure canning as it requires more equipment and experience but not surprisingly it relies on pressure to create a temperature high enough (240F) to safely preserve low acid foods.

Water bath canning, however, is something you certainly get started doing today as it requires no (or very little) special equipment and only a basic understanding of canning.

What you DO need for water bath canning, though, are HIGH ACID foods*. The reason is because microorganisms which can create food spoilage cannot survive in acidic environments especially when they are heated to a high temperature using the boiling water bath (212F). Click here to see a handy chart on the acidity in several fruits and vegetables and definitely check out this post from Food in Jars all about acidity if that interests you!

And now, here’s something you will hear me say again and again while talking about canning: if you use reputable canning recipes and follow the safety requirements, you should easily and safely be able to can jam even if you are new to this. I’ll talk more about this soon but want you to hear it early on :)

Another reason why water bath canning works is that the high temperatures help to drive out air from the jar creating a vacuum seal. As the jars cool, the lids will seal so that air and other microorganisms cannot get inside the jar and the product can safely be stored without the use of a refrigerator. Listen closely and you’ll hear the jars pop! when they seal.

* Friendly reminder from your non-science loving friend: high acidic foods actual have a low pH (less than 4.6) ;)

My Favorite Canning Resources

As I mentioned above, I’m no expert and my main goal is to inspire you to want to try canning and learn more about it. So here are some of my favorite resources for you to learn more about the processes of canning and where I get almost all of the recipes I use for canning. I’ll be referencing some of these resources throughout the series.

Ball Canning: I don’t think it’s any surprise that my go-to for canning jars & lids also has lots of great, trusted recipes and information on their website.

Food in Jars: Marissa at Food in Jars is such a knowledgeable resource for food preservation and writes about it not only on her blog and cookbooks but also is a well-known contributor to lots of food & cooking sites.

Mother Earth News: This post provides lots of links to other resources on canning and food preservation as well as some more in-depth information on the science behind canning and more advanced methods.

National Center for Home Food Preservation: Another resource for more in-depth and advanced lessons on home preservation, including forms such as curing/smoking, freezing and dehydration.

All of the seasonal ingredients we used at the canning party I hosted.

Benefits of Canning

Alright, so now we have a pretty good understanding of why canning works but I am sure you’re wondering why even do all this?!

Sure, people have been using this method of food preservation for hundreds of years but it’s now the 21st century and we have grocery stores and refrigerators so what’s really the point?

Here are some of my favorite reasons for canning:

  • Allows additional harvest to be used and no food goes to waste! Your berries won’t last more than a week if only storing them in the fridge.

  • Provides you with a stockpile of foods to enjoy in the long days of winter when seasonally available foods are few and far between.

  • If using produce from a local farm you are supporting local agriculture and farmers.

  • If you feel like sharing or have a lot extra, homemade canned goods make excellent presents that are sincere and heartfelt!

  • Budget friendly - buying produce in season often means its cheaper and you can use these to create your canned goods.

  • Lessens the environmental impact as the jars are reusable and don’t go in the recycling bin.

  • Connects you to a traditional method of eating and the process lets you slow down - I promise the whole process can be deeply meditative.

  • Personalization - don’t like store bought jam? Try your own combination!

Now, one thing I do want to address is that I think these days, foods that are in our pantries are deemed as “bad” and are morally lower than those in our fridge (which also presents a whole elitist element to wellness but that’s another story for another day).

We think of “healthy” as only being about the freshest fruits and vegetables available. And while I love these things too, sometimes they simply aren’t available!

Maybe you’ve had a crazy busy week and the fridge is bare. Or perhaps it’s that dreadful time in February when there isn’t much seasonally available and if you have to eat any more cabbage you’ll scream. Or maybe financially you can’t afford to constantly be buying organic food products or fresh produce.

In these instances (and so many more) I say: turn to the pantry! Not only are canned foods nutritious (both emotionally and physically), they are in fact often MORE nutritious than fresh options as they are harvested at their peak ripeness and don’t travel miles across the country to get to you (a journey which causes them to lose certain nutrients).

So let go of that pantry stigma, find your own personal reason to try this traditional method and let’s get canning!

A few of the basics (from top right): jar rack, clean towels, jar lifter or tongs with rubber bands, new lids, chopstick to remove air bubbles, candy thermometer, bands, jars.

Equipment You’ll Need

One of the biggest misconceptions about canning is that it requires a lot of fancy equipment when in fact, you probably have most of what you need already in your possession. And if you don’t have some of these things, they are easy to find at your local store or I will show you ways you can hack it together.

Large Stockpot or Water Bath Canner: I have a large 10 quart stockpot that I use for this. You need to make sure that you can cover your jars (standing upright) by at least 1-2 inches of water and allow room for the water to boil. Also, this stockpot is SEPARATE from the pot or Dutch oven you will use to make your jam, salsa or pickled vegetables.

Dutch Oven or Additional Stockpot: You will need a separate pot to make your product and ensuring it is the proper temperature before transferring it to your jars.

Tongs or Jar Lifter: A jar lifter helps you remove the jars from the boiling water while keeping them upright but you can also place rubber bands around a pair of tongs like in the photo above (my personal favorite method that I picked up from Food in Jars).

NEW Lids: New lids are essential to make sure the jar seals properly. You can use either the lids that come with a new jar or buy a pack of lids.

Jars & Jar Bands (can be reused): Because I have limited pantry space (hello NYC kitchen), I typically can things in half pint and 4 ounce jars (especially jams, salsas, etc). Some larger items such as pickled vegetables will require a larger jar, however. Remember that lids and jar bands come in wide mouth and regular sizes so make sure they fit your jars!

Jar Rack: When placing your jars in the boiling water bath, you need to ensure space between the jars and the bottom of the pot. I use a round cookie rack that fits perfectly inside my stockpot.

Air Bubble Remover or Chopstick: Using this tool ensures all air bubbles are removed and therefore cannot create microorganisms inside the jar which can spoil the food. I simply use a chopstick (hence the staining above from a batch of blueberry jam HAHA).

Candy Thermometer: To measure temperature of the water and the jam or salsa you are making (most recipes will require you to get your product to a specific temperature before canning).

Ladle: Self-explanatory (I think) but you’ll need a way to get your product into the jars! Slotted spoons may be useful as well.

Clean Towels: Not going to lie, canning gets a little messy but that’s part of the fun! Just be sure to have a bunch of clean towels available.

Canning Funnel: Or you can use any funnel you are sure your product will fit through!

Of course this is a very basic list and doesn’t include everything you need to every recipe. Be sure to read your recipe thoroughly and have your equipment cleaned and prepped before starting!

While you can reuse canning jars & bands year after year, you must replace the lids in order to make sure the jars seal properly.

Canning Safety Tips & Process

I don’t want to scare you but there are some basics to ensure your end products are edible and clear of any microorganisms. But I promise you, they are totally easy to do and canning is a very safe and fun home project!

  • Be sure to use new lids (the flat part) every time. You can reuse jars and bands (the part that twists on) but the lids need to be new to ensure the sealing ring seals properly. Once a lid has been used though I retire it to my non-canning uses (such as sealing my jars of grains in my pantry)

  • Everything you are going to use (see equipment list below) should be well cleansed (and rinsed) in hot water and soap before using. Before starting any canning project I clean my kitchen sink well, fill it with warm-hot soapy water and let all of my equipment sit in there for a few minutes. I scrub them as needed and then rinse well and let dry on a clean towel.

  • Find and use reputable recipes. Using these ensures you have proper filling amounts, processing times and that your product will have the proper pH to be safely canned using the water bath canning method. Be sure to follow these recipes closely! Small changes can have an impact on the pH.

  • If any of your jars do not seal after 24 hours, transfer them to the fridge to be consumed in the next few weeks (depending on the recipe). You will know if a jar has not sealed if you do not hear the pop after removing from the water and if the top of the lid is still flexible.

  • When you eventually open your canned goods, throw it away if there is any inkling of spoilage such as sliminess, foul or “off” smell or mold growing on top.

Now as I’ve mentioned I am not a canning expert and there are SO many great resources out there about the process for water bath canning so instead of go step by step through the process, I am going to link to some great resources where you can see the process in full!

Food in Jars: New to Canning? Start Here: Boiling Water Bath Canning

Simply Canning: Water Bath Canning

Fresh Preserving: Water Bath Canning

Okay are you ready to get started planning your canning party!? Stay tuned tomorrow when I’ll be sharing my favorite recipes you can make at your canning party and what to serve with them!

And don’t forget if you are enjoying this series to share it with a friend or follow along on Instagram :)