Dec 6, 2016
Since buying my Instant Pot, I've spent a fair amount of time in online groups devoted to pressure cooking, and one question that seems to come up over and over again is: How do I can food in my pressure cooker?
The simple answer is: You can't. At least not safely.
Pressure cookers are not designed for canning. (Although a few pressure canners can be used for both canning and cooking.)
Pressure cookers are smaller and designed for fewer contents (including water) than pressure canners are. Pressure cookers come up to pressure and go down to zero pressure in considerably less time than a pressure canner. While that might sound like a good thing, it actually means canned goods would not be processed for a long enough time, which would lead to your food in jars being unsafe. In other words, a pressure cooker used as a pressure canner won't kill the microorganisms that could make you sick (or even kill you).
Yes, some manufacturers do say you may can in their pressure cookers, but both the National Center for Home Food Preservation and USDA do not recommend them for this use. The risk simply isn't worth the convenience.
Mar 22, 2016
Water Bath vs. Pressure Canning
|The difference is important!|
First, let's define some important terms, so we're all on the same page.
A water bath canner is a large pot with a loose lid. In fact, you can use any large pot for water bath canning, as long as it has a lid and a rack on the bottom that prevents the jars from touching the bottom of the pan.
A pressure canner is also a large pot, but it must be made for the specific purpose of home canning. It's lid fits tightly and has a pressure relief valve and a gauge that helps canners monitor the pressure inside the pot. It is not the same thing as a pressure cooker. (Although some pressure canners may also be used as pressure cookers, no pressure cooker can safely be used as a pressure canner.)
Okay, now that' out of the way, let's talk about not killing your family through home canning.
The Big Fear: Botulism
Botulism is a bacterium that's everywhere in our environment. It loves lows low-acid, oxygen-free, high-moisture environments and it can't be killed by boiling, freezing, drying, most household cleaners, or even by radiation. It's nasty stuff. As Erica Strauss of Northwest Edible Life has pointed out, just a single pint jar of pure botulism would kill everyone on the planet. No wonder home canners are afraid of it.
Thankfully, botulism poisoning is very rare. In the U.S., the Centers for Disease Control (CDC) receive about 145 reported cases of botulism poisoning yearly. Only 15% of these cases are associated with food. However, among those cases 38%, are from improperly home canned vegetables.
There are two ways to ensure your home canned food does not kill somebody (or make them ill). The first involves the acidity level of the food, and the second has to do with heating the food.
Botulism hates a high-acid environment. That means if your canned food is high enough in acidity, botulism can't make you sick. Foods that are safe to water bath can must have a high acidity level - 4.6 or higher. Anything below that level of acidity must be pressure canned, or indeed, it might make someone very, very sick.
(As an aside, the most common excuse for water bath canning low acid foods, like vegetables, is "But my grandmother did it and we're all still alive!" That's rather like saying, "But I drive home drunk every night and I haven't gotten into an accident yet!" And, in fact, many people who can this way do get sick off their home canned food. Not all food poisoning is botulism, after all, and most food poisoning is mistakenly thought a "24 hour stomach bug.")
So, to be clear, jams, fruits, and fruit juices are high acid and generally safe to water bath can. (But always check The National Center for Home Food Preservation (NCHFP) to be doubly sure.) Vegetables, meats, and legumes are low-acid and must be pressure canned. An exception is pickled vegetables, which (because of high levels of acidic vinegar) are water bath canned.
So why does pressure canning work with low-acid foods? Because it gets the temperature of the food up to 240 degrees F. (much hotter than in water bath canning), and botulism can't live at that temperature. Even then, however, that temperature must be kept for a certain length of time for the spores to completely die off.
The Easy Way to Prevent Botulism
Hopefully, now you can see why approved recipes - recipes that have been tested in a lab - are vital to safe home canning. Most home canners have no reliable way to test the acidity of the food they are canning, nor do they have a way to know they've cooked food long enough to kill botulism.
When we hear about home canners giving themselves or others botulism, they've always made egregious choices. For example, in 2013, a Washington man nearly died of botulism after consuming elk meat he'd processed in a pressure cooker (not a pressure canner - first problem) for a far shorter time than he should have (second problem). When the lids started coming off his jars while in his pantry, instead of throwing the meat away, he ate it (fourth problem). Oy! In 1997, an Illinois man came near death after eating home canned pickled eggs. That's right; there is no approved home canning recipe for eggs of any type. And in 2015, someone poisoned everyone at their church picnic (killing one) by serving improperly home canned potatoes. Many news reports hint that the potatoes were canned in a water bath canner, instead of a pressure canner.
Never change a canning recipe in any way, and your home canned foods will be perfectly safe.
As you become more experienced, you will find you can change the spices in recipes like stew, or create your own soup using NCHFP's guidelines. But never change what type of canner you use, or how long the processing time is, or can anything that the NCHFP says shouldn't be canned. (That includes all dairy, eggs, anything with flour, and anything so dense it can't be heated through - like pureed pumpkin or very thick applesauce.)
So how easy is that? Just use approved recipes from a source like Ball or NCHFP. Easy peasy!
Just in Case...
If you simply follow tested recipes, it's highly unlikely you'll ever get food poisoning from your home canned foods. However, there are a few other guidelines you should bear in mind:
* Never store your home canned food with the rings on. Sometimes jar lids unseal. If you leave the ring on the jar, it may reseal; bacteria will enter the jar, and you'll never know the food is contaminated. If you leave the ring off the jar, however, it will not reseal...so when you discover the open jar in your pantry, you will throw the whole thing away, rather than eat it.
* Don't stack anything (other jars, commercially canned food, etc.) on top of jars. Again, this can make lids open and reseal, just like keeping the rings on does.
* Store your home canned food in place where temperatures don't fluctuate and it is neither hot nor cold. (If you're comfortable, so are your jars of home canned food.)
* Pay attention when you open a jar of home canned food. If the seal isn't tight, don't eat the food in the jar.
* If you find a jar with a bulging lid, it is contaminated; don't eat it.
* If you open a jar and liquid or foam squirts out, the contents aren't safe to eat.
* Smell the food while it's still in the jar. If it smells off in any way, do not eat it.
* If there is any mold in the jar, toss the jar.
* If you do suspect any home canned food is spoiled, place the jar and food in a plastic bag, seal it, and dispose of it in the trash. Wipe up any spills with diluted bleach (1/4 cup bleach to 2 cups of water, according to the CDC).
Knowledge is power, my friends. And home canning isn't difficult. It is perfectly safe to use a pressure canner. Just use a trusted recipe!
Jul 30, 2014
Myth 1: There's no way I'm home canning anything. I'm not going to risk making my loved ones sick - or evening killing them with botulism!
The Facts: Modern canning is quite safe as long as you follow a modern canning book, like The Ball Complete Book of Home Preserving or the guidelines at the National Center for Home Food Preservation (NCHFP). The steps are simple and when followed completely, you won't get botulism. (If you've read some recent news stories about home canners getting botulism from their home canned food, please note they did not even come close to following proper canning guidelines! Don't skip steps. They are there for a reason.)
Myth 2: I can in an oven. My grandma did it, so I know it's safe.
The Facts: Oven canning is not safe, and never was. This is because the oven doesn't get the food hot enough to kill all the bad bugs.
Myth 3: Butter is totally safe to can.
The Facts: Dairy products aren't suitable for home canning. Learn more here.
Myth 4: Canning lids contain BPA - a chemical I don't want in my diet.
The Facts: Ball and Kerr lids are now BPA free, as are Tattler lids.
Myth 5: It's okay to store my jars with rings on them. It's also okay to stack jars one on top of the other during storage.
The Facts: Both are highly discouraged; here's why: When you leave the rings on canning lids, or when you put something on top of the jars, those jars may unseal - then reseal themselves. This can result in spoiled food - but you won't be able to tell it's spoiled (unless it happens to grow mold or take on a strange smell - which may or may not happen). On the other hand, if you leave the rings off and don't put anything on top of the jars, if they happen to unseal, you'll know about it! The lids won't be able to reseal because there will be no pressure on them, so it will be obvious there's a problem with the seal. (FYI: It's not often that canning lids come unsealed, but under the right conditions, like exposure to too much heat, they may.)
Myth 6: There's no need to boil or simmer lids. They get sterilized during canning, anyway.
Myth 7: It's okay to can vegetables in a water bath canner. My grandmother did it all the time!
The Facts: There was a brief period where some put up vegetables in a water bath canner. But that was before we knew as much about food poisoning as we do now. In addition:
* People rarely died from this unsafe type of canning because after they opened the jar of canned food, they boiled the vegetables to death. This killed all the bad bugs - but it also made the food mushy and removed much of the nutrition from it.
* We now have bacteria and other bugs in our environment that grandma did not.
* Even in Grandma's day, this was risky. It just isn't worth the risk - especially when you can easily can vegetables in a perfectly safe, easy to use pressure canner.
Myth 8: I don't put my jams, jellies, or tomato products in a canner. I just sterilize the jars, put the food in, put the simmered cap on, and turn it upside down. It seals fine!
The Facts: This is the traditional method for canning jams and jellies. However, a quick 10 minute boil in a water bath canner makes the food safer to eat. It's not difficult or time consuming, so why risk making someone sick with unprocessed jams and jellies?
As for tomato products, it's very risky not to process them in a canner. When you cook tomato sauces and other tomato products on the stove, they don't get hot enough to kill bad bugs.
In addition, modern tomatoes may have less acid in them than old-fashioned tomatoes; lower acid means a greater risk for food poisoning, unless the tomatoes are processed in a canner. In fact, some experts recommend only canning tomatoes and tomato products in a pressure canner, to reduce the risk of illness even further.
Myth 9: I can make up my own recipes to home can. I don't have to follow a recipe that's been tested in a laboratory for safety. After all, the canned foods we buy in a store aren't made from "approved" recipes.
The Facts: First, the commercial canning process is entirely different from home canning. And yes, commercially canned recipes are tested for safety - the recipes just aren't shared with the public and are only safe with commercial canning methods.
That said, it's possible to create safe jam recipes, as long as you understand the important balance required to make jam or jelly. In addition, there is some leeway when it comes to soups, as long as you understand density and that some foods just aren't appropriate for canning. However, it's wise for new canners to stick to approved recipes, such as those found in the Ball canning books or on the NCHFP website. In addition, you may wish to check out the books Putting Up and Putting it Up More by Steve Downdey, which explain the process cottage canning businesses use to come up with their own recipes. (Be forewarned; these books are controversial because they set forth not home canning guidelines, but guidelines used in commercial kitchens.)
Myth 10: I always sterilize my canning jars and lids. It's the only safe way to go!
The Facts: It's almost never necessary to sterilize jars and lids before filling them with food. That's because the canning process itself sterilizes them. Learn more here.
Dec 4, 2013
Canning Jar Top Labels
These are the type of labels designed to fit on the lid of canning jar. You may either glue these labels on top of the lid or simply set them on top of the jar lid and hold them in place with a jar screwband.
* Beautiful, old fashioned labels for blueberry, peach, apricot, grape, cherry, raspberry, strawberry,
|Old fashioned labels from World Label.|
* Simple "homemade" labels
* Colorful stripes
* Black and white Art Deco inspired
* Candy stripes
* Simple "Homemade Just for You"
* Green and blue stripes
* Flower power
* Several styles of vintage labels
* Classy chalkboard style
* Plaid, polka-dotted, and starburst labels
* Pretty fruit labels for berry, cherry, raspberry, and strawberry jam
* "Spread Love" labels and tags
|Mason jar labels from ladyfaceblog.blogspot.com|
* Cute fruit labels
* Colorful polka-dots and stripes
* Christmas trees
* Red and white "Jam Made with Love By..."
* Beautiful fruits: cherry, peaches, lemons, tomato, pear, grapes, pumpkin, strawberry, currents, raspberry, and blackberry.
* Photos of real food: apple, tomato, cucumber
* Simple "Made With Love"
* "Farm Fresh"
* Red, blue, and green gingham
* Snazzy black, white, and color labels
* Flowery black and white
* Colorful leaves
* Green leaves and grass
* Mason jars
* Old fashioned strawberry jam
|Christmas presents and penguins from World Label.|
* Pretty vintage
* Red and white striped, snowflakes, and holly labels
* Christmas lights
* Christmas presents and penguins
Canning Jar Front Labels
These labels are designed to glue on the front of a jar - just like labels on grocery-store purchased canned goods. For best results, print on paper with a sticky back.
* Sweet cherry jar labels
* Cute blue and red "Made with Love"
* Red gingham
|Old fashioned strawberries from Happy Miscellany.|
* Colorful polka-dots and stripes
* "The Jam Labelizer:" choose from several fonts and colors
* Christmas and winter theme labels
* Apple pie
* Old fashioned strawberries
* Fruity labels
* Red and white striped, snowflakes, and holly labels
* Elaborate antique
* Modern blue and gold
Canning Jar Tags
These tags tie on with string or ribbon.
* Cute "What's Inside" tags
|Mason jar tags from Cottage Industrialist.|
* Mason jar tags
* Rustic tags for strawberry, peach, cherry, plum, blueberry, raspberry, mixed berry, damson, and blackberry jams (also orange marmalade)
* Patterned mason jars
* "Spread the Love"
* Cute strawberries
* "Homemade Salsa"
* "Farm Fresh"
* Christmasy birds
* Merry Christmas
* Use old Christmas cards to create jar labels.
* Use muffin liners as decorative toppers. Or use brown kraft paper. Tie with string, or just put a jar ring on.
Aug 21, 2013
One area that many, many canners seem to find confusing is when to sterilize jars.
Why Sterilize Canning Jars?
The only reason to sterilize canning jars before canning is if the processing time is very short. Otherwise, the jars and their contents will be perfectly sterilized during the processing time - assuming you're using an approved recipe from Ball or the National Center for Home Food Preservation. (All canning recipes here at Proverbs 31 Woman are from one of these sources.)
When to Sterilize Canning Jars
It is only necessary to sterilize canning jars before filling them if the processing time is under 10 minutes. Very few things fall into that category: Some jellies, jams, marmalades, and similar preserves, and perhaps some pickles in smaller jars, for example.
Anything that is processed more than 10 minutes is put in clean, hot jars that don’t need sterilizing first.
Jars in the Canner Aren't Sterile
Some people think if they put their jars in the canner and turn on the heat, making the water hot (and perhaps even simmering), they are sterilizing the jars. This is not true. This keeps the jars warm before filling them - which is necessary in order to prevent jars from breaking - but the jars aren't actually getting sterilized. (There are other ways to keep jars warm, too, including in a clean sink of hot water and in a dishwasher that has a hot "drying" temperature. I do not recommend keeping them hot in the stove, since this can lead to temperature fluctuations that can make jars break.)
How to Sterilize Canning Jars
There are people who recommend sterilizing canning jars in the oven or the dishwasher, but the only safe way to get them sterile is to boil them. Here’s how:
1. Fill your canner with water so it comes at least 2 inches above the tops of the jars. Be sure there is a rack in the bottom of the canner.
2. Add the canning jars and bring to a boil. Boil for 10 minutes.
3. Now just leave the jars in the canner until you are ready to fill them. (Don’t take them out of the canner and let them air dry.)
It’s that simple!
Jun 21, 2013
A: Older canning lids did contain a layer of BPA sandwiched in between the metal layers, but new Ball and Kerr canning jars no longer do. Look for lids marked "BPA Free." (Ball actually began selling BPA free lids last fall, so you can check the production date on boxes, too.)
Q: A friend told me I shouldn't store my canned jars with the rings on. I like the convenience; is there really a good reason why I shouldn't?
A: Here's why it's best to NOT to store home canned jars with jar rings on them: If, for some reason, the seal on the jar lid breaks free, the ring holds the lid in place and makes it possible for the jar to re-seal - and then there's no way to know whether or not the contents of the jar are still safe to eat. (While you should always smell the product and look for mold, sometimes food can be spoiled and show no signs of it.) So, yes, you really should store your jar rings elsewhere.
|(c) 2013 by Gretchen Harris.|
A: No. When a canning recipe calls for putting food in hot jars, it means the jars must be pre-heated. Otherwise, the jars may break during the canning process, or the contents of the jar may not reach the temperature required to kill off harmful bacteria. There are several ways to keep jars hot before filling them:
1. Place them in the canner (with both the jars and the canner filled with water) and heat the water until it steams.
2. Place the jars in a sanitized sink full of hot tap water; this will require adding fresh hot tap water periodically.
3. Wash the jars in a dishwasher and keep the dishwasher on the hot dry cycle until you're ready to use the jars.
4. Place the jars in a roasting pan with several inches of water in it and place the whole in a warm oven.
The latter method should not be confused with sterilizing jars in the oven (which is not perfectly effective) or oven canning, which is not safe.
Q: I recently canned something from the Ball Complete Book of Home Preserving and I ended up with fewer pints than the book said I would. Is that typical?
A: It depends on how you determine how much produce to use. If you go by number (for example, 20 tomatoes), you may get more or less finished product because produce varies so much in size. For the most accuracy in how much end product to expect, go with the recipe's weight recommendations (for example, 10 lbs. of tomatoes). Even then, however, the recipe only offers an estimate of how much canned food to expect.
Q: For water bath canners, do you need to only use 2 inches of water?
A: No; you must use more than that. The water in the canner should cover the tops of the jars by at least one inch in order to have safely home canned food.
Check out previous' year's Canning Q & A:
Mar 29, 2013
Alum: In older prickling recipes, alum is sometimes called for to add crispness. However, large doses of alum can cause illness, including nasea and gastrointestinal problems. Therefore, it's no longer recommended for pickling.
|Ball offers approved recipes.|
Ascorbic Acid: The scientific name for vitamin C. When used in canning, it prevents the discoloration of fruits and vegetables.
Bacteria: Microorganisms that are found everywhere. Certain bacteria can lead to serious illness or death in humans and may thrive in low-acid, home canned foods that aren't heated to 240 degrees F. for a specific period of time. This is why low-acid foods (like vegetables and meat) must be canned in a pressure canner.
Blanch: In cooking and canning, to blanch means to place food (usually vegetables or fruit) in a pot of boiling water for a very short period of time, then immedietly place the same food in ice water. The process preserves color and texture and makes it possible to easily remove the skin or peel of certain fruits. (Removing the skin or peel isn't merely for aetetics; the outer part of certain foods is more likely to contain bacteria.)
Boil: Heating liquid until bubbles burst over the surface. See also "Boil Gently," "Simmer," "Full Rolling Boil," and "Boiling Point."
Boil Gently: See "Simmer."
Boiling Point: The temperature at which liquid reaches a boil - 212 degrees F. at sea level.
Full Rolling Boil: Boiling rapidly; stirring does not prevent the liquid from continuing to boil. To obtain a gel in jam or jelly, it's vital to cook at a full rolling boil.
|Boiling qater canner|
Botulism: Food poisoning caused by eating toxins caused by the spores of the bacteria Clostridium botulinum. In canning, using only approved recipes with correct processing times, and using the proper canning technique (boiling water vs. pressure canner) prevents botulism.
Brine: Salt-water (with or without added herbs) used in pickling.
Bubble Remover: A canning tool that's shaped like a stick and is not metallic. To use, it is moved straight up and down in the jar to remove most air bubbles. A handle of any non-metallic utensil (such as a spoon with a long handle) may be used instead.
Calcium Chloride: A natural mineral salt used to crisp food (especially pickles) in canning.
Canner: A specially designed pot used for home canning food. "Canner" may refer to a Water Bath Canner or a Pressure Canner, both of which have very specific uses.
Canning Salt: See "Pickling Salt."
Chutney: Spiced mixtures of vegetables or fruits with vinegar, typically used as a spread for breads or meats.
Citric Acid: A natural acid found in citrus fruits like lemons. Used in canning to prevent the browning of foods or to increase acidity.
ClearJel: A brand name product used as a thickener in canning. Thickeners like flour and cornstarch break down in canning and should not be used. ClearJel does not.
|Dial gauge on a pressure canner|
Cold Pack: To place food inside canning jars when it is unheated and uncooked.
Dial Gauge: On a pressure canner, a regulator that indicates the amount of pressure in the canner. For safety's sake, have your gauge tested every year at a local extension office. Or, buy a weighted gauge for your pressure canner (see "Weighted Gauge").
E.coli: A type of bacteria common in human intestines. A strain, Escherichia.coli 0157:H7, produces toxins that may cause diarreah, headaches, chills, fever, or even death.
Exhausting: See "Venting."
Fermentation: Fermentation is a naturally occurring process caused by yeast. In canning, if yeasts haven't been killed during processing, the food will bubble, become scummy, and break the jar's seal. Some foods are fermented before canning, such as certain kinds of pickles or sauerkraut.
Fingertip Tight: A phrase used to describe how snugly jar ring bands should be. To put a screwband on "fingertip tight," use your fingers to turn the band until resistance is met, then tighten just a little further. Over-tightening bands can result in buckled lids or lids that don't seal. Bands that are too loose may also cause lids to not seal.
Food Mill: A device used to puree cooked, soft food, such as tomatoes or apples.
Funnel: A utensil that sits on top of a canning jar to make packing food into the jar easier and less messy. For canning, it should be plastic, since some foods react with metals.
Gasket: A rubber ring that fits inside the opening of a pressure canner and creates a seal so no steam can escape.
Gel Stage: The point at which a soft spread comes to a full gel: 220 degrees F or 8 degrees F. above the boiling point of water.
Headspace: The empty space between the food in a canning jar and the top rim of the jar. Correct headspace is necessary so food can expand during the canning process, and so a strong vacuum seal can be created, sealing the jars.
Hot Pack Method: When hot canning jars are filled with hot food prior to processing. (Compare to "Cold Pack.")
Jam: A soft spread made with crushed fruit.
Jar Lifter: A tool designed for safely lifting canning jars in and out of hot water.
Jelly: A soft spread made with fruit, then strained so it no longer has pieces of fruit in it.
|Jelly strainer with jelly bag.|
Jelly Strainer: A metal stand with a large ring used for holding a jelly bag over a bowl.
Jelly Thermometer: See "Candy Thermometer."
Kosher salt: A coarse salt without additives like iodine. It is sometimes used in pickling, although (due to variations in granule size) it can be difficult to measure accurately. Therefore, pickling salt is usually preferred for canning.
|Canning lids in a lid rack.|
Lid Lifter: A wand-like tool with a magnet at one end, designed for lifting canning lids out of hot water. Lid lifters are no longer necessary, since modern canning lids don't need to be simmered before using.
Lid Rack: A tool designed to neatly hold canning lids in pots of hot water. Lid lifters are no longer necessary, since modern canning lids don't need to be simmered before using.
Low Acid Food: Food that has a pH higher than 4.6. Meat and vegetables are low acid foods - which must be processed in a pressure canner in order to kill harmful bacteria.
Marmalade: A soft, jam-like spread made from citrus and citrus peel.
Open Kettle Canning: An old fashioned method of canning where a canner is not used. Hot jars are filled with hot food and lids are screwed on. As the jars cool, the lids seal. This method does not adequately heat foods and destroy bacteria and therefore is no longer considered safe.
Oven Canning: An old fashioned method of canning where jars are placed in the oven to process. Because it does not adequately heat foods and kill bacteria, it is no longer considered a safe method of canning.
Oxidation: When fruits and vegetables are exposed to oxygen in the air, they oxidize, or turn brown. Oxidation isn't harmful, but may cause textural changes. It can be prevented by keeping cut fruits and vegetables in a bowl of lemon juice and water as you work with them.
Paraffin Wax: A type of wax used to seal jars in an old fashioned canning method. It is no longer used because it doesn't kill all harmful bacteria.
Pectin: A carbohydrate naturally found in fruit and vegetables. In canning, a powdered or liquid form of pectin is used to gel jams, jellies, and other spreads.
Pickle Crisp: A product that uses calcium cloride (naturally found in some salts) to make home canned pickles more crisp.
Pickling: Preserving food in a vinegar solution, often with added spices. Cucumber pickles are the most common pickled food, but many vegetables and fruits may also be pickled.
Pickling Cucumber: A type of cucumber that is small when mature - typically no longer than 6 inches. For the best pickles, they should be processed immediately after picking off the vine.
Pickling Lime: A caustic white powder (also called "slaked lime") used in some old pickle recipes and designed to add crispness. Because it burns, corrodes, and may increase the risk of botulism, it is no longer recommended for home pickling.
Preserves: A soft spread where the fruit retains it shape and is shiny and transparent. Unlike other soft spreads, preserves do not hold their shape when spooned from the jar.
Pressure Canner: A heavy pot with a lid that locks in place and has a pressure regulator. Used to process low acid foods like vegetables and meat. Pressure cookers - similar looking pots used for cooking food - are not suitable for canning; however, some pressure canners are designed to double as pressure cookers.
Pressure Canning Method: A home canning method used to can low acid foods, like meat and vegetables, safely. Because the steam inside the canner is pressurized, it can exceed the point of boiling water (212 degrees F.), which enables the method to kill harmful bacteria in low acid foods.
Pressure Cooker: An air tight pot that cooks food with pressurized steam. Pressure cookers are not the same as pressure canners and should never be used for canning.
Processing Time: The amount of time filled jars are heated in a boiling water canner or pressure canner. Processing times are tested to ensure the contents at the center of the jar reach a temperature that kills off harmful bacteria, and vary according to jar size, contents of the jar, and whether or not the jar was hot packed or cold packed.
Raw Pack: Filling canning jars with unheated, raw food prior to processing them in a canner.
Relish: A pickled food made from chopped vegetables and/or fruits. It is cooked in vinegar and may or may not contain sugar. It is used as a condiment.
Screw Band: A metal circle used to hold a canning lid in place on a canning jar while the jar is being processed. Once the jar is completely cool and sealed, it's best to remove the screw band.
Simmer: To cook just below the boiling point. Bubbles will form in the pot, but will only burst occasionally on top of the liquid.
Slacked Lime: See "Pickling Lime."
Sterilizing: Killing all microorganizsms. In canning, jars don't need to be sterilized before being processed in a canner unless the processing time is 10 minutes or less. To sterilize jars, fill them with water but don't put on lids. Place them in a canner filled with water; bring to a boil and boil for 10 minutes.
Table Salt: A fine grained salt commonly used at the dining table for seasoning. It usually includes anti-caking ingredients and iodine, which can cause cloudy brine or darkened fruit. Pickling salt is preferred for canning.
Vacuum Seal: The state of negative pressure that allows home canned jars to seal and prevent spoilage. When the jar is heated inside the canner, the food and air inside it expand, pushing air out of the jar. When the jar cools and the food inside shrinks, a vacuum forms. The sealing compound on the underside of home canning lids prevents air from re-entering the jar.
Victorio Strainer: A tool that separates the skins and seeds of fruit. It also purees the "meat" of the fruit. It is commonly used for making applesauce and tomato paste.
Weighted Gauge Pressure Canner: A type of pressure canner that has a three- or one-piece weight on the lid that allows steam to vent. The steam causes the weight to rock back and forth during processing, which indicates the correct pressure has been achieved for safe canning. Unlike dial gauges, which should be tested every year for accuracy, a weighted gauge can be used without special testing.
May 23, 2012
Q: I was told it's best not to can on ceramic top stoves. Any workarounds?
A: It's true; canning is strongly discouraged on a ceramic or glass top stoves. Here's why: Because these stove tops can crack at high temperatures, they are designed to never go above a certain heat level. This means the burners don't stay at a temperature that's high enough or consistent enough to kill bacteria that causes food poisoning in canned goods.
Often you'll hear you need a flat-bottomed canner for ceramic or glass stove tops, but the truth is, this may not solve the high/consistent heat problem - especially when the heat sensor on the stove turns off the burner; even if you turn the burner right back on, you've cause a heat fluctuation that could be problematic.
Some folks use a flat bottomed stock pot with a well fitting lid in leiu of a boiling water bath canner. They place a wire cake rack in the bottom, so jars don't touch the bottom of the pot and break. This might work fine, but you'll have to test it on your particular stove.
To test any stove for canning ability:
1. Fill the stock pot or canner with water bring it to a full, rolling boil. If the water won't come to a full boil, the stove can't be used for canning.
2. If the water comes to a full boil, keep it there for the length of time required by the canning recipe you're using. If the stove won't keep the full boil going, the stove can't be used for canning.
Other things to watch out for:
* The pot musn't be more than 1 inch wider than the burner.
* Be sure to carefully lift the canner/pot off the stove; never drag it, as this could damage the stove top.
* If the stove has an automatic shut off, it's almost certainly unsuitable for canning.
If your ceramic top stove is unsuitable for canning, you could purchase a new or used electric coil burner or gas stove and put it outside, just for use when canning. Or you might be able to use a camping stove to can outside, if the stove has enough power to pass the test mentioned above. I've heard the Coleman 2 Burner Propane Grill /Stove works, but I have not personally tested it.
Q: I've seen a lot of blogs with directions for canning butter; is this safe?
A: No. Scientific testing has found no way to home can dairy products (including butter) in a way that effectively kills off dangerous bacteria.
I once knew a lady who canned butter, despite this fact; she stored it in a a very cool, dark area of her home. She didn't have any problems with the butter keeping - until one hot summer when her air conditioning stopped working. Then all her canned butter spoiled rapidly. This means the canning process was doing nothing to preserve the butter; it was keeping it in a very cool location (basically, refrigerating it) that kept the butter good.
Instead of canning butter, I recommend freezing it, learning to make it from scratch (it's easy with a mixer), and/or purchasing commercially canned butter powder or ghee.
Q: I've heard they are bringing back pint and a half jars; I want them for canning asparagus! Where can I buy them?
A: Yes, pint and half (24 oz.) jars are now being made again - and they are perfect for canning asparagus, longer beans, whole carrots, and such. You can purchase pint and a half jars direct from Ball. Amazon carries them, also, and many stores that carry canning jars will introduce them as the canning season comes to full run, including ACE Hardware. Be sure to process pint and a half jars using the quart processing times given with the recipe.
Q: I want to can my jam in pint jars, not half pint jars the recipe gives processing times for. For how long should I process the pint jars?
A: You're right to be concerned about how long to process jars of a different size than the recipe calls for. Failing to do so can result in food that's dangerous to eat because it hasn't been heated well enough to kill off dangerous bacteria. With jams and jellies, use the same processing time for half pint and pint jars. (And don't decrease the processing time when using quarter pint jars.) For other types of foods, consult one of the Ball canning books or the National Center for Home Food Preservation for appropriate processing times.
Be sure to check out "Canning Q & A" from 2011 and 2010, too!
Aug 15, 2011
A: I recommend starting your canning career with a hot water bath canner because it's cheaper to purchase. Most people also find a water bath canner less intimidating (it's just a big pot, after all). Just remember, you won't be able to can soups, meats, or veggies - unless you pickle those veggies. This is a safety concern; a water bath canner can't bring low acid foods to a high enough temperature to make them shelf stable.
The two first projects I recommend are some kind of pickle (click here for a super-easy method) or tomatoes. Pickles are easy (just be sure to can the freshest produce you can find) and tomatoes are not difficult, yet so much tastier than store bought.
For step-by-step water bath canning instructions, click here.
Q: I've been using a water bath canner, but I'd like to do some soups and things. But my friends all agree that using a pressure canner is just - well, scary. What do you think?
A: For some reason, many people find pressure canners intimidating. Maybe it's stories of them blowing up in grandma's kitchen (something that won't happen today, unless you blatantly don't use the canner correctly) or maybe it's just that dial gauge sitting on top of the canner. But I encourage you to take the plunge. I was nervous the first time I used a pressure canner, too, but after my first batch I realized pressure canning isn't so different from canning with a water bath canner. Pressure canners also keep the kitchen cooler, which is nice during the summer.
Q: How long do home canned foods last?
A: According to the U.S. government, one year. However, home canned foods can last many years. Mostly it's a matter of quality, taste, and nutrition; the longer the jar sits, the more the quality declines. Low acid foods (mostly things you'd use a pressure canner for) last the longest; for example, their is a true story about a 118 year old can of meat that was eaten safely (by a cat).
Q: I had an incident last week where a few of my jars broke in the canner. Why did that happen?
A: First, I want to assure newbies I've never had this happen in 10 years of canning. There are a few reasons this could happen, however: 1. If jars have cracks in them. 2. If you don't use a rack on the bottom of the canner. 3. If use non-canning jars are used. 4. If jars are exposed to rapid temperature changes.
It's true canning jars can take greater temperature fluctuations than ordinary glass jars, but they still should be warmed and cooled gradually. If you pour hot contents into a cool jar, or if you put jars filled with cool food into boiling water, the jars may break. So be sure the water in the canner isn't boiling when you put jars in it, and always keep jars hot while they are waiting to be filled. You can do the latter by putting jars in a canner filled with cool water, then bringing the water to steaming, or by placing the jars in a sink of hot water, or by washing the jars in the dishwasher and keeping them hot in the heated (drying) cycle.
Q: What causes seal failures? I recently had a few jars not seal.
A: There are actually quite a number of reasons lids might not seal, all of which are preventable:
1. Over- or under tightening screw bands; they should be just tight.
2. Not wiping the jar rims clean with a fresh cloth or paper towel; any bit of food or debris on the jar rim makes a seal impossible. (This includes bits of cloth or paper from your towel.)
3. Jars without smooth rims; before using them, always run your finger over the rims of jars to ensure they don't have cracks or chips.
4. Leaving an incorrect amount of headspace; you don't have to get out a ruler and measure, but if you leave only 1/2 inch of headspace when the recipe calls for 1 inch, you will have seal failures.
5. Not allowing a pressure canner to vent or exhaust 10 minutes before timing processing.
6. Not getting lids warm enough before placing them on jars; the sticking agent on the lids needs to soften before being applied to a jar. Barely simmering the lids in a saucepan does the trick.
7. Allowing the temperature in the canner to fluctuate during processing.
8. Re-using canning lids; they are considered suitable for only one use.
9. Using screw bands that are bent, warped, or rusty.
Q: Can I can fruit without sugar? What about jams and jellies with lower sugar?
A: In home canning, sugar does not preserve fruit. However, fruit canned in water tends to have very little flavor. For those limiting the amount of sugar in their diet, use a light syrup of 5 cups of water for every 1/2 cup of sugar. It's also possible to can fruits with fruit juice or honey. For more information on this technique, read Canning and Preserving Without Sugar by Norma Macrae.
Jams and jellies made with less sugar can result in a watery product, but you may lower the overall sugar levels in the food by using a "no sugar needed" pectin (available in the canning section of stores like Walmart). Macrea's book also covers jams without sugar.
Q: When I can my fruit, it floats. I notice yours does, too. What's up with that?
A: Floating fruit is normal and is especially prevalent if you can fruit without cooking it first. Fruit is full of air, and when it is cooked or canned, it will loose air. This results in jars that don't look nearly as full as they did before you packed them with fruit. Instead, the fruit floats at the top of the jar. It is not a safety issue. (So why not just cook the fruit first? Because it will loose nutrients. It also adds another step to the canning process.)
Q: I bought a rocker gauge for my pressure canner, but it didn't come with instructions. How do I use it?
A: If you don't want to have your pressure canner's dial gauge tested every year, you should buy a rocker gauge for your canner. For complete info on this, read this post. To use the rocker gauge, remove the weight vent that came with the canner and replace it with the rocker gauge. The gauge has three parts. If you use just the bottom piece, it will bring the canner to 5 lbs. pressure. If you use the bottom and middle part on top of each other, they'll bring the canner to 10 lbs. pressure. Add the top part, and the canner will come to 15 lbs. pressure. When the gauge rocks steadily, you know you've reached the right pressure.
Be sure to also check out last year's Canning Q & A.