Canning Basics

Jars filled with apricot, blackberry & peach jam

It's a lot of work, but the enjoyment and satisfaction felt when you dine on the fruits of that labor are well worth it.  
Although it requires effort, it is not as hard as you might think.  On the other hand, it is not a game to be played sloppily.  Among the potential hazards associated with home food preservation, botulism is the dominant concern.  And it's not something to be toyed with - according to one source, one milligram of the toxin produced by this bacteria can be fatal to humans!  Furthermore, there are evidently no home-tests for botulism, and it does not typically cause visible damage or changes in the canned food product.


Bottom line - home food preservation fans have a serious responsibility to themselves and their dinner guests.  If you are as enthusiastic about this project as we are, please spend some time on the website of the National Center for Home Food Preservation.  This center is part of the Extension Services System (a cooperation of universities across the United States of America), and all their recipes have been lab-tested and adjusted to maximize food safety.  They also discuss in detail projects and procedures that are not recommended.  Even better, their recipes are tasty, simple and can easily be multiplied to meet the scale of your project.

If you are new to canning, we recommend starting with tomatoes, peaches, jam or pickles (read pickles post here)- they are about as easy as it gets.  This is due in part to the fact that high-sugar fruits and high-acid foods (like tomatoes and pickles) do not typically require processing in a pressure canner.  Pressure canners require more up-front investment, more precision, and may be more intimidating if they are your first experience with canning.

Water-bath canner (left); pressure canner (right)

Water-bath canning, on the other hand, is typically a low-cost investment, and is fairly straightforward.  To get started, prowl thrift shops (esp. when it's not harvest season) in search of canning equipment.    For most water-bath projects, you will only need the items pictured*: 

Over the years I have managed to scavenge three canning kettles, each complete with their essential metal "basket" (your jars should not be in direct contact with the kettle or each other), from various 2nd hand stores.  I've also scored piles of good jars - in this case good is not a relative term.  When it comes to canning it is important to use jars made for this purpose.  The "canning lid fits it" test is not good enough, as many commercial jars can be fitted with canning-style lid-and-ring tops.  

There are two factors to consider when selecting jars, both of which point to using only canning jars.  First, if the lids do not fit securely, you risk a poor seal and potential food poisoning.  Second, jars not made for canning may be more likely to break in the canner, causing a disheartening loss of your precious foodstuffs and a parallel sinking sensation of wasted time.


Next, each jar requires a two-part lid consisting of a threaded metal band (or ring) and a NEW self-sealing lid.  Re-use of lids is only acceptable for leftovers or when freezing foods.  A new lid is essential for ensuring food safety when canning.  Just think back to the last time you pried the lid off a jar of something home preserved.  In order to get the lid off, you typically have to bend it, and it remains misshapen ever after.  Without a new lid, you won't get a proper seal.


And, just a hint - when you put a lid and ring on a jar with something hot in it (i.e. jam, etc.), it may make the "pop!" without even being processed in the canner.  Do not be fooled!  Processing is not something to skip - it's not just the seal you need.  You also need the entire contents of the jar exposed to a certain temperature for a certain amount of time, in order to kill potentially harmful bacteria.  So, if you hear it pop, don't stop.  Process it in the canner for the time specified in the recipe, remove the jars to cool, and then do your happy dance when you hear those lids pop.

Finally, decide what you want to make.  If this is actually your absolutely-first-time-ever, make jam.  Jam is HIGH on our list of worthwhile canning projects for a number of reasons:

• It is a high-return value-added project (usually a fraction of the cost of a store bought pint-1/2 pint of organic jam)
• You can control the amount of sugar (if you use universal pectin, such as Pomona's)
• You can make lots of small jars, in contrast to canning whole fruit or tomatoes, when it is more work-efficient to use larger jars.  Small jars make it easier to happily part with your homemade jam - give it away and people RAVE!
• If you are going to go to the trouble, getting more than just canned fruit or veggies for your trouble helps motivate you to do it again.

Good luck!  Bonne chance!  

Have fun!

Handy Links:

• Start here: National Center for Home Food Preservation (link also posted in our Resources page)
• Think canning is old-fashioned?  According to this NPR article, 43% of canners are between 18-34 years old.
• Interesting recipes from "across the pond" - See this BBC link for some highlights from this BBC article.