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I grew up in Los Angeles and the only fruit bearing plant we had was a grizzled old white peach tree. In the city, nobody canned! Canning was something Martha Stewart did at her Connecticut farm. Until I was in my 20’s I had no idea that canning was something real people did. But now we live in the Pacific Northwest, and we’ve inherited a garden which produces more fruit in a given week than two people can consume no matter how hard they try. Most of June we had pie for breakfast and still barely put a dent in our harvest. It was time to start “putting up” as folks here say.

In the beginning I did a lot of winging it. My husband, who minored in chemistry and has a more methodical mind, reminded me that being loosey goosey with food safety was in no one’s best interest. It took some research, but after the first few tries, we made pretty much flawless jams and jellies out of everything from currants to mulberries. Here’s what we learned along the way about doing preservation right:

Use a Recipe

As fond as I am of shooting from the hip when it comes to the culinary arts, canning could be a dangerous kind of chemistry. I used to think, you just boil some fruit, drop in sugar to taste and … jam. But I found that there’s a lot more to it than that.  Some recipes require lemon juice because certain fruits don’t have the required acidity to preserve well. For any preserve product that needs to set, there’s a delicate balance to getting it to gel correctly. For the most part pectin is what will give jams and jellies their consistency.

Pectin is the fickle god of the preservation process, you must treat it with reverence and respect. It’s a complex carbohydrate that’s naturally present in many fruits, and in the right circumstances, pectin clings together and gives preserved fruits their pleasantly gummy texture. But some fruits need a little extra help, and for added pectin to actually cling it needs just the right chemical circumstances - the perfect ratio of sugar to water, etc. How much pectin and when you add the pectin depends on a number of variables including what kind of pectin you use. Pectin also can’t gel in batches that are too large. The back of the box is your key!

Most pectin also requires Willy Wonka levels of sugar, so I tend to buy the low sugar pectin that’s pre-mixed with calcium, and always follow the recommended ratios. I didn’t once and my entire harvest of red currants became syrup. To be fair, the syrup has been very useful in mixed drinks, especially the one I mixed after realizing it wouldn’t set. 

Heat it Up

To sterilize the jars, you’ll need to remove the lids from the jars, wash them and put them in a pot to just barely simmer, then put the jars themselves in a large stock pot completely submerged in boiling water, leave them boiling for at least ten minutes. Make sure there’s a rack between the jars and the bottom of the pot so water can circulate all around.

Top it Off

Fill the jars with preserves up to about a quarter of an inch from the top. Then replace the lids and screw them down just a tad, and send them back into the boil bath for at least another ten minutes. Boiling will raise the temperature of the contents, kill any bugs, push out any excess air, and start the sealing process.

No Touching!

Canning needs to be sterile, so it requires a few specific, and relatively inexpensive implements, most of which allow you to work at high temperatures without having to touch anything.

The Pop!

The best and most satisfying part of canning, other than the taste of homemade preserves, is the pop of the jar top as it is sucked back down once the air inside cools. After you take your finished jars out of their final boil bath, you set them out to cool and wait for the sound. This is how you know that your seal worked.  If you miss the pop for whatever reason, you can unscrew the metal band at the top and lift the jar from the edges an inch or so off the top of the counter. If your seal didn’t take, you just have an excellent opportunity to eat more jam, never a bad thing.

The magic of preservation is that it stops the inexorable forward rush of time, in a very obvious and practical way - but also in a more subtle way. Smell and taste are the senses which live closest to the memory. I’ve lived in Oregon long enough now to have had the transcendent experience of tasting homemade jam in the winter months. Like Proust’s madeleines - in the cold and rain, a spoonful of blueberry jam can transport you back to the long, warm evenings of June. It’s just enough to pull you through to the next spring. Happy canning!