It was not so very long ago that canning was commonplace enough that most people had at least seen it done. That's not true anymore, hence this little photo-primer. Like my jam-making instructions, there's no recipe included here, though the procedures apply to pretty much any recipe that calls for a boiling water canner. Which is to say things like jams, jellies, whole fruit preserves, tomato sauces and most relishes...the so-called "acid" foods. "Non-acid" foods, things like whole vegetables and meat sauces, are canned according to an entirely different method requiring a pressure canner. I don't do any of that, preferring to leave it to the pro's. As for any recipe that you intend to can, make sure it comes from a reputable source, and follow all instructions to the letter.

In general, here's how the boiling water canner procedure goes. Start by determining how many jars you'll need, then wash them thoroughly in hot soapy water. A dishwasher works great for this.

Arrange them on a rack just to the side of the stove where you're making your whatever-it-is.

Put your lids on to simmer very gently in a small sauce pan. The idea here is to have the lids as sanitized as possible without boiling them per se. Vigorous boiling can damage the rubber on the undersides of the lids and ruin your seal.

When your jam, butter, relish or chili sauce is ready, ladle it into the waiting jars, leaving 1/4-inch space at the top. Looks messy dunnit? It is.

Once all the jars have been filled, go around to each one with a clean paper towel and wipe away any residues, bits of fruit or seeds that might interfere with a good seal.

Using your little magnetic canning wand, pluck a lid out of the hot water and and place it on top of the jar.

Once that's done, put on the ring and screw it down onto the jar. Once it's all the way on, the general rule of thumb is to give the ring one good firm twist to tighten it. Don't go nuts with this since you don't want to bend the threads on the ring (though you probably won't be able to hold the jar long enough to put that kind of muscle into it...the things are hot with preserves inside).

Packed jars at the ready, proceed to your canner. Mine I put on a propane-fueled burner on the patio. Why? Firstly because I have a glass-topped electric range which can't support the weight of a canner. Second, because the burner puts out something like 36,000 BTU's of heat. Wide open, it'll bring a full canner's worth of water to the boil in about 15 minutes. Third, because canning outdoors makes me feel like a true-blue old school Kentuckian.

So then, with the water at full boil and the rack raised, I put in my packed jars, being careful to insert them in order at the 12:00, 5:00, 10:00, 4:00, 7:00 and 2:00 positions. You can put one in the middle after that if you wish. Why be so uptight about the loading sequence? Because the wire rack isn't terribly stable. You want the thing as balanced as possible at all times to avoid a tip-up, splashing and a potential cracking of the jars should they crash against the bottom of the canner.

Using oven mits or kitchen towels, lower the rack into the canner and release the handles, which will then fall in.

Cover the canner with the lid and keep the jars immersed for as long as the recipe stipulates. Remember that a minute in the canner only counts so long as the water is boiling. I don't have a problem with my canner water cooling down, due to the heat of the burner. However most home canners will take a minute or to to recover once the jars are put in.

When time is up, take off the top and either a) raise up the rack or b) just reach in with your jar graspers and fish out the jars, as I'm doing here. Pick up the jars one by one...

...let the hot water drain off, then up-end each jar to give the inside of lid one last dose of heat (I don't know if this is strictly necessary anymore, but it's the way the old-schoolers did it).

Set the jar down in a place where you won't have to move it until the next day and...you're done! Over the next several hours you'll hear the pink, ponk of the lids being sucked in by the vacuum environments in the jars. It is a most satisfying sound, I can tell you. The following day, check all the tops by pressing down on them firmly with your finger. If there's any give to them at all, you've got a bad seal. No matter...eat it! Or pass it along to a friend or neighbor as a factory reject. They'll love you for it, I promise.

Blueberry-cinnamon jam to be precise, though these general instructions can be applied to just about any kind of jam. It all starts of course with fruit. Most people use fresh fruit, fresh picked especially, but I've known more than a few people to use frozen. Frozen? Yes, frozen. It doesn't make terribly much sense from a cost standpoint, but if you live in an urban area, love homemade jam, but don't have easy access to orchard-fresh fruit, it'll do. It can even be superior depending on the fruit and the time of year.

So then, it all starts with a good rinsing of your berries. Once they're air-dried, I find it's helpful to pour them out onto a sheet pan and roll them around a bit. Errant stems will usually pop off as you do this, plus it makes overripe or damaged fruit easy to spot.

Here I'm pouring them off into my pot and you can see what's left behind (I didn't see half of these when I started):

You want to use a deep pot so there's plenty of room for any froth to rise. Here I'm using a six-quart dutch oven which I find works just about perfectly.

Now: mash. This step of course releases juice, but it's also critical for exposing the interiors of the blueberry skins, which is where your pectin will mostly come from. A potato masher works great, this one is sort of a combo masher-cutter:

Now's a good time to add any flavorings you might want. In this case, a half teaspoon of cinnamon:

An important trick to getting a good gel is heating the fruit slowly at first (to tease out the pectins), then cranking the flame up at the very final stage. Start by bringing the mashed fruit to a gentle simmer over medium-low heat (forgive some of these photos, they're a little dark and blurry and/or steamy, but YOU try taking perfect pictures in low light conditions over a pot of boiling jam!).

In goes the acid (lemon juice)...

...and the sugar...

...then we turn up the heat to medium-high. What you're after here is a short, hard boil for about three minutes or so. That's the point at which you want to start checking for gelling.

Which, admittedly, is harder than it sounds. This is were most first (or second or third)-time jam makers tend to get confused, since a "gel" is by no means an obvious thing. The mixture doesn't suddenly turn to thick syrup, in fact a "gelled" jam still looks quite thin to the untrained eye (this is because the jam is very, very hot). So what are you looking for then? The answer is a subtle change in viscosity from water-like to something a bit less that water-like. Also, a change in color to a slightly darker, richer hue.

I know that sounds maddeningly ambiguous, but that's jam-making for you, and why most people nowadays use packaged pectin (if you were using packaged pectin, this would be the time to add it: stir it in, wait 30 seconds, then quickly kill the heat so as not to destroy its thickening ability). But then I'm a like-grandma-used-to-make kinda jam maker, so I does my best and takes my chances. Having tried several methods, I think the spoon-drop test is the most reliable. What you're looking for is a bit of a subtlety, what some people refer to as "sheeting" of the hot jam...the slow-ish convergence of two drops into one large drop before it falls off the rim of the spoon (the larger the spoon the better for this). Two drops falling right next to each other is also a dead giveaway of a gel — and it frequently happens with blueberry jam after 2-4 minutes of hard boiling. An accumulation of jam near the bottom lip of the spoon is also a strong indicator. Look here:

See that dark area at the very bottom of the spoon just above the drip? You won't see that unless your jam is very near, or at, the gelling point. Prior to that point the hot jam just pours off the spoon like water, leaving virtually nothing behind. At the gelling point the jam still pours off easily, but has a somewhat higher viscosity. Drips fall off rather slowly leaving an accumulation on the rim. Anyway that's the best I can describe it. If in doubt just quit the cooking after 5-8 minutes with a berry jam, or after 20 with stone fruit jams. Your jam may not be the ideal consistency — thought it just might — but at the very least the end product will be useful as a topping.

Feel like giving it a try? Oh come on...don't be a sissy. What would great grandma say?