You can buy almost any food in a can, from pineapple slices to ravioli to Spam. While most canning that’s done at home is done with glass jars, not metal cans, the verb that describes the process remains “can.” But language is dynamic, constantly evolving to keep pace with the changing meanings it conveys. And recently, I’ve noticed a new verb in circulation.
Overheard at a coffee shop: “Let’s jar tomorrow after farmers market.”
Via email: “What are you jarring these days?”
At the farmers market: “They jarred on their first date.”
This linguistic revolt reveals some of the energy and creativity being focused on home economics these days, but how the jarring’s done remains more important than what you call it. And given that harvest season is jarring season, it’s time for me to crack open my jar of knowledge on the act itself.
This conversation carries liability concerns, because it’s possible to get very sick and even die from poorly jarred food — not the kind of jarring experience we want. So if I seem extra-anal today, it’s because I don’t want anyone to get hurt, or sued.
The science of jarring recognizes two primary categories of contents: high-acid foods, like fruits and pickles, are less susceptible to spoilage; low-acid foods, like veggies not pickled in vinegar solution, beans, and meat, carry a higher risk of spoilage. High-acid foods can be jarred in a water bath, which is simply a pot of boiling water into which sealed jars of food are submerged. Any pot that holds enough water will suffice, but most people use a 5- or 8-gallon enameled kettle.
Low-acid foods have to be jarred in a specialized pressure cooker called a “pressure canner.” Unlike the pressure cookers used for cooking, pressure canners have gauges that measure their interior pressure in pounds per square inch. Different foods have to be pressure-jarred for different amounts of time, and both time and pressure requirements increase with your elevation. Below 1,000 feet, 10 lbs. of pressure is standard for most foods; add a pound for each thousand feet above 1,000. Also, add 10 minutes to the processing time if you’re above 1,000 feet, and a minute more for each additional thousand feet. After processing your jars as directed by your recipe, turn off the heat and allow the pressure to drop to zero before opening the unit.
Speaking of recipes, there are many to be found in books, magazines, and online — not to mention in this column. Recipes exist for pretty much anything you could want to put in jars, including condiments, juice, ready-to-eat meals, and pie filling.
There are two parts to the jarring package, in addition to the jar itself: the lid, which contains a rubberized ring that seals against the rim of the jar, and the ring, which is screwed onto the jar’s threaded neck to hold the lid in place. Jars and rings can be re-used, but lids should only be used once. (A box of 10 new lids costs about $2.)
The jars have to be squeaky clean and free of cracks, with unblemished rims. It’s best to use jars intended for jarring, aka Mason jars, like the Ball or Kerr brands, though many people reuse mayonnaise or pasta-sauce jars. While canning rings and lids will fit many such jars, the glass from which they’re made isn’t necessarily up to the temperatures and pressures that jarring can produce. If these jars do survive jarring and the lids seal, then you got away with it, and the result will be the same as if you’d used Mason jars. But it’s likely that some reused grocery jars will break in the process, turning the water bath or pressure cooker into a soupy sea of unpreserved, unrecoverable, wasted produce. Mason jars, though stronger, also can crack. To avoid this, keep the jars and their contents as warm as possible prior to lowering the jars slowly into the boiling water. A pair of “canning” tongs really helps in dealing with hot jars and boiling water.
Both lids and jars must be sterilized before use. The jars can be boiled, steamed, or baked at 220 degrees. Sterilize lids in a pot of water, bringing the water to the pre-boiling point where little bubbles start to float up, then removing the heat before the water boils. Leave sterilized lids in the hot water, covered, until use.
Once your jars are sterilized and ready for filling, a common rookie mistake is to overpack them. The term “headspace” refers to the empty space between the top of the food and lid. If you don’t leave enough headspace, there won’t be enough air to contract as the jar cools, and the lid might not seal. I know you want to pack a lot of food in the jar, but you have to leave enough headspace. Not all “canning” recipes specify headspace, so my rule of thumb is to not let anything stick above the point where the rounded glass of the jar joins the vertical, threaded neck.
After removing the finished jars from the pressure cooker or water bath, set them aside and allow to cool. If you did it right, you’ll be serenaded by a chorus of pings as your jars seal, one by one.
Store your sealed, labeled, and dated jars in a cool place and inspect each jar before and after opening. Look for bulging lids, discolored contents, contents that bubble upon opening, escaping gas upon opening, and off odors. The jar’s contents should be tossed at any suspicious sign. While you may end up tossing some innocents, playing it safe will keep you going for many jarring years to come. Years of salsa with your big greasy breakfasts, pickles, catsup, and mustard with your sandwiches, grape juice with your dinner, and pie filling for dessert. That’s the kind of jarring schedule that I, for one, can get used to. •
A peck of pickled peppers
Cut the stems off the peppers, and a hair off the top so the vinegar can enter. With jalapeños sometimes I slice them into 1/2-inch rounds. Use as many different types of pepper as you can get your hands on, but avoid bell peppers and New Mexico-style chiles. Also, thick-skinned peppers are better than thin-skinned.
I like to add sliced carrots and onions, too, but they aren’t necessary. If adding those, you can go up to 1:1 with the carrots, but don’t add more than 1/4 part onion to one part pepper. I also like adding a sprig or two of oregano to each jar, Mexican-style.
Wash and sterilize your jars. To each quart, add a tablespoon of mustard seeds (I make a mix of brown and yellow mustard seeds and spoon from that), a teaspoon of salt, and your sprigs of oregano. Pack your jars, leaving an inch of head space. Figure on 2-3 cups of brine, aka the liquid in the pickle jar, for each quart jar. The brine is 1:1 water to vinegar; the vinegar portion is 1:1 cider vinegar to white wine vinegar. Thus, the brine is 2 parts water, 1 part cider vinegar, 1 part white-wine vinegar. (You can skip the white-wine vinegar, flavor-wise, but pure cider vinegar makes the jars look a little murky). Heat the brine. As it’s heating, add sugar, up to a cup for every 10 cups of brine. The exact amount is entirely at your discretion. I like enough sugar to take the edge off the vinegar, but not actually make it sweet, though a little sweetness won’t hurt. As soon as the brine starts to simmer, remove it from the heat.
Heat some plain water, which you’ll use to warm the jars in just a few minutes. Put the packed jars in a baking pan, and pour in the brine; pour extra-slowly if the jars have cooled post-sterilization. Cover the peppers et al. by at least half an inch. Make sure the rims are clear of mustard seeds and anything else, and screw on sterilized lids and rings. Slowly pour hot water into the baking pan that the jars are in, as deep as the pan will allow. Heating the jar bottoms like this will keep them from cracking when you lower them into the boiling water bath. Let the jars warm for a minute, and then slowly lower them into the water bath, which should be at a rolling boil. Cover, and process 10 minutes. Remove jars and leave them at room temperature until they all “ping.” If any don’t seal after an hour, re-process or keep them in the fridge.
— Ari LeVaux