No! Pressure cooking and pressure canning are NOT the same thing, and many people are confused by the differences (after all, they sound so similar). If you're going to use a pressure cooker or pressure canner, it's important to know what each one does--in fact, your life may depend on it.
Here, we look at pressure cookers and pressure canners: their similarities and differences, how they're used, the overlap between them, safety issues, and more. It's not hard to see how they're different, but if you have a pressure cooker or canner in your kitchen or are planning on buying one (or both), these are critical issues to understand.
Pressure Cooker Vs. Pressure Canner Summary:
A pressure cooker is used to cook foods at high pressure. It has a locking lid to hold in pressure but no gauge to keep it at a constant pressure.
A pressure canner is used to preserve foods in mason jars for long term shelf stability without refrigeration. It has a locking lid and a gauge that holds a steady pressure. Pressure canners are larger than pressure cookers so they can hold 4 or more quart-sized mason jars.
You can use most pressure canners as a pressure cooker, but you can't use pressure cookers as a pressure canner. But if you want to do pressure cooking and pressure canning, you should really have both because pressure canners are large and heavy, making them awkward to use for food.
What Is Pressure Cooking?
Pressure cooking uses a sealed pot containing liquid to cook food; liquid is necessary to create steam, which creates pressure inside a closed vessel. Steam creates pressure higher than atmospheric pressure, which raises the boiling point of the liquid--from 212F to approximately 250F, depending on your pressure setting and altitude--so food cooks faster.
If this isn't clear, here's a definition of pressure cooking from Wikipedia:
Pressure cooking is the process of cooking food under high pressure steam, employing water or a water-based cooking liquid, in a sealed vessel known as a pressure cooker. High pressure limits boiling, and creates higher cooking temperatures which cook food far more quickly...Almost any food that can be cooked in steam or water-based liquids can be cooked in a pressure cooker. Modern pressure cookers have numerous safety features to prevent the pressure cooker from holding too much pressure. After cooking, the steam pressure is lowered back to ambient atmospheric pressure, so that the vessel can be opened. A safety lock prevents opening while under pressure on all modern devices.
The principle is the same for both stovetop pressure cookers and electric pressure cookers (Instant Pots).
Due to the higher pressure, food cooks up to 70% faster than non-pressurized cooking, which saves time and energy.
Pressure cooking works for any cooking method that uses liquid, so what a slow cooker takes several hours to do a pressure cooker can do in under an hour.
You can also cook beans, rice, grains, and pasta, braise meats (an excellent method for tough cuts), and make soups, stews, stocks, and broths.
If you have a rack or steamer, you can cook meats and vegetables together for quick one-pot meals. A rack also makes it possible to cook foods inside jars, like garlic confit. (This is not the same as pressure canning, so foods cooked in jars must be refrigerated.)
Pressure cooking uses steam pressure in an enclosed pot to cook food: meats, beans, grains, soups, stocks, and more. The higher pressure causes food to cook about 70% faster than standard methods.
What Is Pressure Canning?
Pressure canning is a food preservation method used for canning primarily low-acid foods in mason jars.
According to Wikipedia:
Pressure canning is the only safe home canning method for meats and low-acid foods. This method uses a pressure canner — similar to, but heavier than a pressure cooker. A small amount of water is placed in the pressure canner and it is turned to steam, which without pressure would be 212 °F (100 °C), but under pressure is raised to 240 °F (116 °C). Based on the recipe, the canner is heated until the correct pressure is reached, and the jars left for the appropriate amount of time (charts have been published with times and pressures). The heat is turned off, pressure reduced, canner opened, and hot jars carefully lifted out and placed on an insulated surface (towels, wood cutting board, etc.) and out of drafts to cool.
Because canned food is only safe when cooked to an exact temperature for an exact amount of time, pressure canners need to hold a more accurate pressure than pressure cookers. Many have gauges that show the pressure, as in the photo above. Some have weighted gauges similar to pressure cookers, but able to hold a more accurate pressure:
You don't need a pressure canner for high-acid foods because the high acid content combined with the heat of a water bath kills pathogens, making the food safe.
You can use a pressure canner for high-acid foods, but you don't need to. A hot water bath in an open pot is all you need to can high-acid foods safely.
Never can low-acid foods without a pressure canner. It is not safe because an open water bath can't get hot enough to kill the food-borne pathogens in low-acid foods. Pressure is required to raise the temperature enough to kill pathogens effectively (i.e., the temp has to be 240F or higher--only attainable in a pressure cooker).
See the next section for a list of low- and high-acid foods.
Pressure canning is a food preservation method used primarily for low-acid foods. Pressure canning use mason jars for long-term, shelf-stable storage and requires exact times and pressure to ensure that all food-borne pathogens are destroyed. Pressure canners are larger and have a more accurate gauge than pressure cookers to achieve this.
What Are High-Acid and Low-Acid Foods?
If you want to preserve foods for long term, shelf-stable storage, you absolutely need to understand two things:
- The difference between a pressure cooker and a pressure canner (and how to use each)
- The difference between high acid foods and low acid foods (and how to preserve/can each).
In short, low acid foods require pressure canning for safe preservation, and high acid foods do not.
This means you can use a pressure cooker to can high acid foods, though there is an easier way (discussed below).
For low acid foods, you must use a pressure canner with an accurate pressure gauge. You must also follow exact procedures to ensure the food is safely and properly preserved.
What Constitutes High and Low Acid Foods?
According to the Home and Garden Information Center of Clemson University:
- High acid foods have a pH factor of 4.6 or below.
- Low acid foods have a pH factor of 4.6 or above.
In most cases, you don't need to know the exact pH of your food. Following proper canning procedures and guidelines is enough to ensure safe results.
However, some foods can be tricky. For example, tomatoes have traditionally had enough acid to can without a pressure canner. But some of today's strains of tomatoes are so sweet that they require additional acid or a pressure canner for safe results.
If you're not sure, you should err on the side of caution and use a pressure canner.
High Acid Foods
High acid foods include:
- Most tomatoes
- Most fruits, including apples, berries, peaches, pears, plums, grapes, oranges, and pineapple
- Pickles of any variety (vinegar makes any food high acid)
Low Acid Foods
Low acid foods include:
- Some fruits, including figs, papayas, most melons, and some strains of tomato
- Meats, poultry, seafood (including shellfish)
- Most vegetables, including asparagus, artichoke, green beans, broccoli, cabbage, beets, carrots, corn, cauliflower, garlic, onion, potatoes, squash, and yams/sweet potatoes.
For more details, see the link above, or contact your local extension service (especially if you live at an altitude above 1,000 feet) or check out the USDA canning guidelines for a more extensive list and exact guidelines.
High acid foods include most fruits, most tomatoes, and pickles. High acid content makes foods safer to can, so you can use the water bath method; a pressure canner is not required.
Low acid foods include meats, seafood, beans, and most vegetables. They require a pressure canner for safe canning, as well as following strict canning guidelines to ensure that pathogens are destroyed.
Summary: Differences Between a Pressure Cooker and a Pressure Canner
Both pressure cookers and pressure canners use steam pressure, but you cannot use them interchangeably. Here are the important differences between pressure cooking and pressure canning:
-Used for cooking meals (soup, stew, beans, etc.)
-Pressure is not as accurate as on a pressure canner, so not safe for canning most foods.
-Smaller than a pressure canner.
-Can use for canning high-acid foods, but small size makes them not a great choice.
-Used for shelf-stable food preservation.
-Has a gauge that holds an accurate pressure for safe canning.
-Larger than a pressure cooker to accommodate jars (up to 4 quart-sized mason jars).
-Can use to can all foods safely, but necessary for just low-acid foods.
Can You Use a Pressure Cooker to Can Food?
To be absolutely safe, the short answer is no, you can't use a pressure cooker to can food.
Here's why: Safe food preservation requires food be cooked at a constant temperature, time, and pressure to ensure that all pathogens are destroyed. This is essential for safe, long-term, shelf-stable storage.
Pressure cookers aren't accurate enough to hold a constant pressure.
However: This matters most for low-acid foods because it's harder to kill the pathogens in them. This means you can use a pressure cooker to can high-acid foods and know that they will be shelf stable--but you probably won't want to, for a few reasons.
One, pressure cookers are too small to hold a lot of jars, and most aren't large enough to hold any quart jars, so using them for canning is practical only for small amounts of food--and remember, it has to be high acid food (there's a list above).
Two, and more importantly, it may not be safe. Unless you know the exact pH of your food--that is, its acid content--you can't be sure that you're preserving it safely. For example, some sweet strains of tomatoes need to be pressure canned because their pH is too high to be safe (this wasn't always the case for tomatoes, but it is today).
Three, high acid foods are easy to can in a water bath. You just need a big pot, a few tools, and some mason jars, and you're good to go--no futzing around trying to make your small pressure cooker work. This canning set with pot and tools is a great way to get started with water bath canning.
(We talk more about water bath canning below.)
Finally, remember that just because you use a mason jar to cook something in a pressure cooker--garlic confit, omelets, or oatmeal--doesn't mean it's preserved for long-term storage. Unless you've followed proper canning techniques and guidelines for preservation, food is not shelf stable and should be stored in a refrigerator.
You can use a pressure cooker to can high-acid foods, but the water bath method is easier; pressure cookers are also too small to fit very many jars, so they're only good for canning small amounts of high-acid foods.
Can You Use a Pressure Canner to Cook Food?
Yes: you can use most pressure canners to cook food (without jars). Pressure canners are more accurate than pressure cookers, so it makes sense that you can cook anything in them (and that it doesn't go the other way).
If a pressure canner is usable for food, it will probably be called a "pressure cooker/canner" rather than just a pressure canner--like this pressure canner. But just because a product is labeled as a cooker/canner doesn't mean you should use it for both. There are a few reasons why it's not a great idea.
First, pressure canners are larger and heavier than pressure cookers, so for most people, they're a pain to use for pressure cooking.
Second, cleaning a huge, heavy pressure canner of food residue would not be at all fun--and necessary if you're using it for canning.
Third, you don't need the accuracy of a pressure canner to cook food.
So while you can pressure cook food in most pressure canners, they aren't really designed for it.
For best results and easiest maintenance, you should have a pressure cooker for meals, a pressure canner for low-acid food preservation, and a large pot and canning tools for high-acid food preservation.
Yes, you can use a pressure canner to can high-acid foods, but it's much easier to use the water bath method. In fact, if you're new to preserving food by canning, we recommend getting started with a water bath and doing only high-acid foods until you feel confident in your canning skills. Then you can decide if you want to go all out with a pressure canner and can your own low-acid foods (meat, most vegetables, beans, etc.).
If you do decide to use a pressure canner for food, follow the instructions for the pressure canner, and follow the standard safety instruction for pressure cookers. For example, don't fill the canner more than two-thirds full of food, or more than half full for foaming foods (like beans).
You can use most pressure canners as pressure cookers, but because they're larger and heavier, they aren't practical for pressure cooking.
Are Pressure Cookers and Pressure Canners Safe?
Yes: modern pressure cookers and pressure canners are quite safe.
You may be hesitant to buy a pressure cooker or pressure canner because you've heard stories about them exploding and even killing people.
This has happened, but most of these tragedies happened decades ago. Modern pressure cookers and canners are very safe. They have redundant safety features that ensure safe operation.
Even if they malfunction, they are unlikely to explode.
The biggest reason pressure cookers and canners malfunction is user error. You must be careful to understand and follow all guidelines, recipes, and safety instructions.
For example, if a pressure cooker valve gets clogged, it's almost always because the pot is too full--never fill a pressure cooker more than two-thirds full, or half full for foaming foods like beans.
Modern pressure cookers and pressure canners are extremely safe. Most failures are caused by user errors like filling the cooker too full. Always read all operating instructions and safety guidelines before using a pressure cooker or pressure canner. For canning, also be sure to understand and follow all canning guidelines.
How Does Altitude Affect Pressure?
If you live more than 1,000 feet above sea level, you need to understand how high altitude affects pressure cooking and canning.
At high altitude, water boils at a lower temperature--and the higher the altitude, the lower the boiling point.
This means that pressure-cooked foods and pressure-canned foods will need more cooking time than at lower altitudes.
If you don't adjust cooking time for altitude (when necessary), you risk undercooked food when pressure cooking, and canned food that isn't safe to eat because the pathogens weren't destroyed.
Here's a simple chart showing boiling points for higher altitudes*:
*Chart from friedalovesbread.com
This USDA High Altitude Cooking Guide explains how altitude affects cooking times, and how much you need to increase cooking time for different altitudes.
If you love higher than 1,000 feet above sea level, be sure to understand and follow all guidelines fo pressure cooking and canning at your altitude.
The Two Methods of Canning
There are two methods of canning food: pressure canning and water bath canning.
Pressure canning is used for low-acid foods and requires a pressure canner (thus the name). You can use it for everything, but it's only required for low acid foods like meat, most veggies, and beans (see list above).
Water bath canning is used for high-acid foods. With this method, you simply use a large pot with a fairly small amount of boiling water, plus a few tools to handle hot mason jars.
Water bath canning is fairly easy, and a safe way to get started canning. Here's a great article from The Prairie Homestead on how to get started with water bath canning.
You can get started canning with just a stock pot, but it's much easier if you have the right tools to handle hot mason jars. This inexpensive water bath canning kit is a great way to get started.
Both methods require that you read and follow all instructions and guidelines to ensure you produce safe foods. Canning isn't difficult, but you do have to be careful and understand the process.
And to reiterate, notice that a pressure cooker is not considered a canning tool. It's too small for either type of canning unless you are preserving a small amount of high-acid food; they are not safe to use for low-acid canning.
Water bath canning is for high-acid foods, which have fewer pathogens.
Pressure canning is for low-acid foods and requires a pressure canner (NOT a pressure cooker).
If you are new to canning, the water bath method and high-acid foods is the easiest way to get started.
Why Is it So Important to Follow Canning Procedures?
Simple: because you can die if you don't.
To pressure can safely, you should follow recipes and procedures exactly. Many extension services provide guidelines you can find on the Internet or by calling your local extension service. This is particularly important if you are at an altitude of 1,000 feet or greater because altitude affects the boiling point, and thus the safe canning time for many foods.
For overall guidelines, here is the USDA Complete Guide to Home Canning, or see instructions for your water bath canning or pressure canner.
Not following canning guidelines and procedures can kill you.
What to Look for in a Pressure Cooker
Basically, you want a safe pressure cooker that's easy to use and large enough for the amounts of food you want to cook--we recommend erring on the side of larger because you can only fill a pressure cooker two-thirds full (of half full for foaming foods like beans). You may also want to do meal prepping or make stocks in your pressure cooker, which requires a large size. (And remember, you can cook small amounts of food in a big pressure cooker, but you can't cook large amounts in a small pressure cooker.)
For a more detailed discussion on how to buy a pressure cooker, see our Fissler and Kuhn Rikon reviews. Even if you don't want to invest in one of these premium brands, there is good information on how to choose a pressure cooker.
Here are our recommendations for stovetop pressure cookers:
Fissler 6.4 or 8.5 Quart with glass lid (about $230/$240)
Kuhn Rikon 8.45 Quart with extra wide base (about $400)
Kuhn Rikon 7.4 Quart deep sauce pan shape (about $240)
Presto 8 Quart Stainless Steel (about $100; we do not recommend Presto's aluminum models).
For an electric pressure cooker:
Instant Pot Duo Plus 9-in1 Electric Pressure Cooker (6 quart, about $100).
A good pressure cooker should be safe, easy to operate, and large enough for how you want to use it. We recommend not going smaller than 6 quarts, and 8 quarts is even better for meal prepping and making stocks and soups.
What to Look for in a Pressure Canner
Important features of a pressure canner are similar to a pressure cooker: they should be safe, easy to use, and large enough to suit your canning needs (a pressure canner should be able to fit a minimum of 4 quart-sized mason jars.)
One other requirement is accuracy, so we recommend buying a pressure canner with a dial that shows the exact pressure. Weighted gauges are also accurate, but they're harder to use.
We really like the All American brand: they're made in the USA and built like a tank. The 10.5-quart size is a good size unless you're really into canning:
All American 10.5 Qt. Pressure Canner (About $240)
Unfortunately this size is sold out on Amazon, but you can see the other sizes and compare prices:
All American Pressure Canners on Amazon (About $400 to $650).
If you don't want to make this kind of investment in pressure canning, Presto makes highly-rated canners for a much more reasonable price:
Presto 16 Qt Aluminum Pressure Canner (About $135).
We don't like aluminum for pressure cookers because aluminum can transfer metallic flavors to your food. But for canning, aluminum is perfectly fine.
A pressure canner should be safe, easy to use, and large enough to fit at least 4 1-quart mason jars at a time. A dial gauge is the most accurate and easiest to use, so we recommend this type of pressure canner, but weighted gauges are also safe to us, and usually less expensive.
Summary of Pressure Cookers Vs. Pressure Canners
To summarize pressure cookers vs. pressure canners:
- Pressure cookers are used to make food/meals.
- Pressure canners are used to preserve low-acid foods in jars for long-term, shelf-stable storage.
- Pressure canners hold pressure more accurately than pressure cookers, which is essential to kill pathogens in low-acid foods.
- You can use pressure canners to preserve high-acid foods, but a water bath is an easier method.
- You can use pressure canners to cook food, but you can't use pressure cookers to preserve low-acid foods.
This article is a basic guide to the differences between pressure cookers and pressure canners. It is not meant to be a guide to safe canning. Please consult more detailed resources for canning instructions, and follow all recipes and guidelines carefully. Food-borne pathogens can kill you, so following all guidelines and safety instructions is essential to safe canning.
Thanks for reading!
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