The Lost (and found) Art of Canning

The Lost (and found)

Art of Canning

by Guest Blogger Graeme Smith

When someone tells you that the art of canning has been lost, don’t believe them. The art of canning still exists, as the sales of canning supplies attest. What has happened is that some people who want to can, have failed to find teachers, which is another thing entirely. The instructions on how to can have been printed, there are old recipe books that still have recipes that deal with canning, but these haven’t made it to the internet, perhaps because the best-loved recipes have too much “found art” decorating their pages because of their heavy use, that, well, an OCR would have a field day trying to understand it.

The main art of canning is the art of making a vacuum. Long before vacuum cleaners, people were sealing their produce into jars, and protecting them by evacuating all the air out of them. The secondary art is the art of Luis Pasteur, how to make a stab at producing a sterile environment for the produce, so that introduced germs don’t get in the food. If you look at all modern canning supplies you will find that they have improved over the years, but the same rules apply. Sterilize everything, then put your produce into a jar, create a vacuum in the jar, while putting the top back on.

Now, here is the problem, Canning jars almost always now have metal lids, so you can’t sterilize them in your microwave. You will actually have to stress and strain over a hot stove. Horrors! Fem-Libbers were horrified, perhaps there is a reason why they quit doing it! However in this day of role reversals, there is no reason why a Man can’t spend a few hours toiling over a hot stove, so perhaps it is time for Men to learn canning!

In our world of microwavable plastic dishes, and freezers large enough to park a truck in [storage freezers], and consumer driven just-in-time supplies shipped from half way round the world, there is only one reason to learn canning. It frees you somewhat from the dependency on the supermarket supply chain, which is the first thing to go in an emergency, and it also frees you from the financial burden of buying produce you can grow in your own back yard. The money you save, you can spend on computer equipment, or making stuff, or just on toothpaste if that is what you need.

The main caveat of canning in our world of massive time-wasting entertainment, is that well, it takes HOURS to do it right. So, look at it as a cheaper form of entertainment (especially if you are a guy), you get to putter around in the kitchen for hours, and your wife who is usually very territorial about the kitchen, might even thank you for it, after she gets over her mad at all the dishes it takes. Or, alternately look at it as a social event, get together canning parties, where everyone pitches in, and the job gets done so much faster. From the Hacking Ethos, think of canning as the ultimate Hack of the Food Storage problem that has plagued man from time immemorial.

Believe it or not, most of the things that are bad for you, food-wise have been developed as ways of making storage of food last longer. Think about it, oily potato chips, candy, desserts made with high sugar and fat fruit fillings, alcohol, vinegar, ketchup and mustard, all those preservatives: all that was developed to keep the food on the shelf a little longer because the store didn’t have Just-in-time delivery, and didn’t like paying for spoilage. OK, OK, I know food preparation for storage existed centuries before we even had stores. The native North Americans used storage techniques like smoking, drying, pounding fruit, and dried meat into powder. Hams are really just a way of preparing pork, so it stores well. The High Salt diet comes from attempts to protect sea food between its catch and the cannery. Almost every form of preservation has resulted in health risks of one sort or another.

Canning has its own risks, as my grandmothers generation would insist. Hot water is dangerous, and sterilization techniques of the day were to boil everything in hot water. The main reason it will be safer for you than for my grandmother, is simply that you will be canning mostly for yourself and friends, and can probably do it away from the environment with squalling babies, and playing children because the Kitchen, which we often no longer need, have been segregated in the newer houses. In my Grandmother’s time, the kitchen WAS the living room, there was no separation. But there is nothing inherently toxic in boiling water, and re-useable glass jars. Of course if you want to go whole hog, and can find a canning machine, you can even get to canning in tin cans, but that has implications for recycle-ability, and issues with the coatings on the tin.

So let us start with preparing the food. Food for canning must come in a form that will stay preserved for a reasonable length of time. Your natural vegetables come from the garden with a certain amount of dirt and are teaming with micro-organisms that will eventually eat the food before you do, if you leave it in a warm environment. (Why do you think we have fridges and freezers?) The plant itself while it was alive, had the ability to protect itself from much of the damage it would have had from being eaten alive by micro-organisms and other little pests. So, if you get it fresh enough, and in good enough shape, you can be fairly sure that most of the germs will be in the layer directly in contact with the dirt. So first wash them off with a vegetable brush, something that can get into all the crevasses and remove the dirt.

Fruits are often much more delicate, but give them a good rinse at least , and scrub with something less destructive. Some fruits are naturally acidic and this helps because their acid will limit the types of germs that can grow. All the citric fruits, and even Tomatoes are acidic… why do you think so much ethnic food has tomatoes in it? Some have thick rinds, or skins, that need to be removed because you don’t usually eat them. However have you ever heard of Lemon or Orange zest? That is the secret name of ground up lemon and orange rinds… A grater might give you access to a secret ingredient to use to prepare other foods later, and you can always throw a baggy of it, into the freezer to use later. Much of it will simply have to be composted, or horrors, thrown away.

Jellies and Jams are simply concoctions where non acidic fruits, which have a checkered past even for canning, can be safely stored. However the need for high levels of sugar, is no longer as much of a consideration as it was in the past. A dietetic solution might be found that lets you get the same effect, without adding sugar.

Combinations of highly acidic fruits with non-acidic fruits have their roles since the highly acidic fruit can actually protect the non-acidic fruit to some extent. This is why my Grandmother often used to combine the highly prolific, and (virtually impossible to remove from the garden once started) stalks of the rhubarb plant with things like strawberries and raspberries. Thus she was able to make quite delicious pies well into the winter, and early spring. Of course my mother achieves the same thing with a freezer, but that is not about preserving either our heritage or the stuff in the garden.

Preparation is all, in canning. Nothing should be canned that has not, at least, been blanched, and often the canning should include some preservative syrup or something that can protect the food from damage. Some things like crab apples have their own preservatives (in this case, pectin) built into them, and may just need the preservative concentrated by “Reduction.” This is easier today than it ever was before, if only because you can do the Juicing step in a juicer. This is also why your tins of fruit always include a sugar syrup. It protects the food during the canning step. The sugar really isn’t needed today, in the time of micro-wave cooking where irradiation of the food kills off most of the germs. (You should however check your microwave for its evenness of cooking; many seem to have blind spots where they no longer evenly cook.)

Once you have prepared your food, the next step is how to get it into the canning bottles without letting germs in. There are some tricks but the main thing is to have a pot that is big enough that you can immerse the bottle and have about 2 inches of water above it. It might be nice to have a set of Tongs, so you don’t have to take a chance on hurting yourself getting the canning jars into, and out of the boiling water, and oven gloves are necessary for the last step. There used to be big pots called “Canners” that we used for this type of thing, but somehow they quit adding them to the “Pot Sets” that we usually buy for newly-weds. A quick work-around is to use a taller pressure cooker for the same job. (This will also help with canning vegetables because they are required to have a harder vacuum, and as such, using the higher heat of the pressure cooker, when it has the top, and weight installed, makes for a better seal.)

So lets start with the black art of canning. First sterilize everything. Second create a vacuum, and third put the top back on without breaking the vacuum. Seem magical? Hardly. Canning uses a simple expansion co-efficient to get the effect. (Expansion you ask? Well yes, in fact it is the expansion of air in the jar from the heat of the boiling water that is used if you don’t have your own vacuum pump.) Once we have boiled everything, including the lids, for a while, and used grandmother’s canning recipe suitably changed for our times, (get rid of the sugar, salt, fats, and preservatives that aren’t needed,) the next thing is to put the now mostly sterile food into the bottle leaving a significant amount of air at the top. About 1/2 inch to 1 inch is enough. Then you put the lid on, but stop. The hidden art of canning is NOT TO FULLY TIGHTEN THE LID. (Yet) That is the trick. You can make sure that you are doing this correctly by closing the lid, then backing it off, about 1/2 to 3/4 turn depending on what type of canning jar you use. While it is possible to use Jam Jars again, make sure they have the plastic seal, and since they don’t have as many threads as actual canning jars, be conservative about how much you back the top off.

Ok, so the jar is semi-sealed. Now we immerse it in the boiling water in the Canner. The boiling water does two things, it seals the bottle away from the air, in an almost sterile environment, and it heats the bottle up so that the air in the top expands and leaks out of the bottle. When you are canning with multiple bottles it is nice to have a sort of wire rack that separates them so they don’t crash into each other, but if you have to, you can seal one canning bottle at a time, it’s not really cost effective since you are paying for the electricity to heat the bottles whether or not you use all of the canner to heat them, but sometimes a little waste heat is to be expected.

Once the bottle has been in the water for a while, probably about 15 minutes or so, take a look at it. If you see bubbles escaping it, it isn’t ready. If there are no bubbles, use your tongs to fish the bottle out, and use the oven mitt to immediately close the lid hard. Let the bottle sit on the counter or better yet on a cooling rack, and let it cool. If you got it sealed, there is usually a sort of dimple on the metal top, that indicates vacuum. This should be sucked down by the vacuum into the jar so it is level or below the rest of the lid. If not, you screwed up. Crack the top, pry off the lid, if it is separate, and put the jar back into the canner/deep pot, to boil again. (Often you may find a chip on the edge of the bottle or a defect in the seal plastic around the lid, that is breaking the vacuum. Where these are found, replace the defective part and try again.)

The real trick in canning is not preserving the food, it is making the food tasty and safe without bowing to your Grandmother’s assumptions about the need for sugar, salt, fat, and preservatives. Canning your own food frees you from the fact that the food industry is not at all interested in doing away with all that [the extra salt, sugar, fat and preservatives], because they would have to redesign the industry to do so. Besides, except for the electricity and the seeds you need to grow your own garden, the major cost is time, and it is time well wasted.