Pressure Cooking: What, Why & How

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What is pressure cooking? Pressure cooking uses steam pressure to cook food inside a sealed pot, which causes the food to cook quickly. It’s an easy way to prepare an entire meal without much effort. Plus, you’ll only have one pot to clean!

I love spending time with my family, but sometimes we get so wrapped up in fun we’re having that dinnertime sneaks up on me. Using pressure cookers means I can enjoy the maximum amount of time with my family while still cooking them delicious, healthy meals.

Before you give pressure cooking a try in your kitchen, I’ll tell you all about it. We’ll go over:

  • The history of pressure cooking
  • Different types of pressure cookers
  • How you use a pressure cooker
  • Why you should use a pressure cooker

The History of Pressure Cooking

Pressure cooker history started in the 1600s, when Denis Papin, a French physicist invented the first recorded pressure cooker. Though the technology has existed for 400 years, this cooking method didn’t become commonplace until World War II.

Papin's steam digester
Old illustration of steam digester invented by French physicist Denis Papin in 1679. Original, by unknown author, was published on L’Eau, by G. Tissandier, Hachette, Paris, 1873

The first pressure cookers needed the stove to heat them.  They had a safety valve to safely release steam and prevent explosions.

Many people, including myself, have used pressure cookers in this way to this very day.

Yet pressure cookers leveled up in 1991 when the first electric pressure cooker was invented. These appliances functioned independently of the stove by using their internal heating element.

Since then, pressure cookers have improved even more as manufacturers added programmable features to the electric versions. You can set a timer, and some models even let you choose the pressure setting.

How do pressure cookers work?

Pressure cookers work by combining heat and pressure. Just by increasing pressure, the heat increases.

Further the increased pressure lowers the amount of heat needed to cook your food as pressure does some of the work.

Types of Pressure Cooker

While technology has progressed, you can still choose to buy a stovetop pressure cooker. It might seem like a no-brainer to choose an electric model instead, but there are pros and cons for both types of pressure cookers.

Electric Pressure Cookers

Electric pressure cookers are the best choice if you want to be hands-off with your meal prep. Toss all of your ingredients into the pot, seal the lid, pick your settings, and that’s it! The pressure cooker does all of the work and turns off when the cooking finishes.

Electric multi cooker

The latest electric pressure cookers have programmable features, like choosing different pressure options for your food. Some even had pre-set menu buttons like soup, poultry, rice, and yogurt. This means you can pop in some beans, pick the right option, and not think about it again.


Before you choose your pressure cooker, consider what meals you’ll be making. Newer pots make it easy for you to sear and brown meats in the same pot. Some also give you the option to slow-cook foods.

My favorite electric pressure cookers have the option to delay your cooking start, adding flexibility. You can set the time limit for cooking your recipe, then program it to not start for up to 24 hours.

If you like the idea of an electric pressure cooker, I’ve reviewed some different ones:

One thing to be clear on is that electric pressure cookers are not air fryers. Air fryers use circulating hot air, much like a convection oven, not pressure, to cook. I’ve written a guide explaining more of the differences between pressure cookers and air fryers.

Stovetop Pressure Cookers

If you could plug in an electric pressure cooker and let it go, why would anyone use a stovetop pressure cooker? These pots require more attention, and you have to manually release the steam valve, which can be difficult for beginners.

High pressure aluminum cooking pot with safety cover

Still, there are a few advantages to using a stovetop pressure cooker. It can sear foods, which adds great flavor to any meat you might prepare.

Stovetop pressure cookers reach a higher pressure level, quickly reaching the boiling point and cooking the food faster. Since this pot uses heat from the stovetop, it cooks more evenly than the electric heating element.

Another bonus to using a stovetop pressure cooker is that it looks like a huge stockpot with a fitted lid, so it’s easier to store in your cabinet with your other pots and pans. On the other hand, electric pressure cookers are pretty bulky and take up a lot of storage space.

Electric vs stovetop pressure cooker

Generally, stovetop pressure cookers are more straightforward, smaller, and cheaper.  If you know what you are doing, they’re a great choice.

If you like the idea, then check out my guide to stovetop pressure cookers.

How to Use a Pressure Cooker

Using a pressure cooker is a straightforward process. 

Add your food and liquid to your pressure cooker pot according to your recipe, or follow the guidelines included with your appliance. Close the lid and make sure the valve is in the right place before you start cooking.

You need to ensure the lid is securely in place.  Pressure cookers are constantly trying to blow their one lids off!

Pressure Cooker With Vegetables

Set your pressure cooker. If you have an electric model, you can input the pressure and time or select a pre-configured option. If you’re using a stovetop model, choose the pressure setting on the top and then turn the stove’s heat to high.

Wait for the pressure to build up in the pot. If you’re using an electric model, then the screen will automatically show the cooking countdown. If you’re using a stovetop model, you’ll turn the heat to low and use a timer to monitor cooking time once steam starts leaving the cooker.

For stovetop pots, once your cooking timer goes off, you release the pressure on the pot. To do this safely, first turn off the stove.  Then lift the little valve over the steam release. Wait until steam stops coming out of the vent before removing the lid.

Steam blowing out of a pressure cooker

Never overstuff your pressure cooker! There’s a limit of how much food it can hold, so make sure you’re following the instructions to the letter. If you overfill the pot, food might block the pressure valve, which could be dangerous.

When it comes to how much water to add, it depends on what you are cooking.  For rice, for example, a good rule of thumb is one cup of water for every cup of rice.

Too much water will negatively affect the flavor of your meal and make sauces too runny.  Not enough could leave your food dry or even be dangerous.

How Much Pressure Is in a Pressure Cooker?

Pressure cookers work by raising the boiling point of water in the pot. The boiling point of water is not some fixed thing but depends on the pressure.  The higher the pressure, the higher the boiling point of water.

Pressure in the cooker is generated as some of the water boils.  As a gas, water takes up more space than as a liquid, increasing the pressure.

Before I go on, if you want a bit more information on the physics of pressure, check out this video:

Pressure in a typical cooker changes the boiling point of water from 100°C (212°F) to 121°C (250°F), cooking the food faster. The steam’s pressure pushes the moisture into the food, which helps tenderize it and preserve flavor.

The high setting on pressure cookers is 10 to 12 PSI, which means pounds per square inch. To put this pressure into perspective, you should know that car tires have 30 or 35 PSI inflation, and they can support more than 2,000 pounds! 

Think of how it feels to be 30 feet underwater without scuba gear to equalize the pressure. This feeling is equivalent to 12 to 15 PSI. Imagine that pressure in the context of food, and you can understand how these appliances cook so efficiently.

Pressure cookers also have low settings that range from 5.5 to 7 PSI. This pressure option lowers the temperature to 110°C (230°F), while the higher pressure option gets closer to 118°C (245°F).

Why Use a Pressure Cooker?

Most people, myself included, use a pressure cooker because it can prepare meals in next to no time at all. 

Rice cooks in just a few minutes, as do apple chunks for homemade applesauce. Even beans and chickpeas cook in less than an hour, and you don’t have to soak them beforehand.

How Much Faster Is Pressure Cooking?

A pressure cooker is, on average, 30% faster than other methods of cooking.

You might need a little time to get used to your pressure cooker. If you’re using an electric model, you can rely on the settings to tell you how long to cook various foods. 

If you’re using a stovetop version, you’ll want to find specific guidelines for your food to make sure you’re cooking it long enough.

While you can check the food in the oven or stir what’s in a pan, you have to wait it out once you start your pressure cooker. I know it might be tempting to release the pressure valve, open the lid, and check the status of things, but this messes up the cooking time and might ruin your dish.

Health Benefits of Pressure Cooking

Pressure cookers are energy-efficient ways to cook because they work quickly and use steam to tenderize the food. It’s also a healthy way to prepare food. Many people think cooking at a higher temperature damages a food’s nutrients, but there’s no truth to that myth.

Boiling or steaming vegetables in an open pot damages their nutrient content because the water pulls out the good stuff, and then we dump the water out before serving the veggies. Using less water in a pressure cooker means fewer nutrients leak out, so your veggies stay healthy and flavorful.

Is It Better to Slow Cook or Pressure Cook?

Slow cookers are the opposite of pressure cookers; they simmer meals over several hours instead of using high heat and steam for cooking quickly. You can prepare your meal in the morning and leave your slow cooker on all day, so you come home to a delicious hot dinner.

Close up of a slow cooker working on kitchen shelf
Some slow cookers, like this one, have glass lids so you can more easily check the progress of your food.

Slow cookers are useful appliances to have if you want to turn on the machine and let it cook all day. They used to be the best option to have a hot meal without standing over the stove at the end of the day. 

However, now pressure cookers can make similar meals in less time, so choosing one over the other depends on your cooking preference.

Is Pressure Cooking Healthy?

Yes. The pressure cooker needs less heat, and helps conserve vitamins and minerals.

Remember that cooking is a destructive process and all forms of cooking will destroy some of the nutritional value of food. That’s why raw diets can be popular.

But cooking also destroys bacteria, that’s why we do it! Pressure cooking is one of the healthier ways of doing this.

Are Pressure Cookers Safe to Use?

High pressure cooking sounds dangerous, and there are elements that can be dangerous.

But pressure cookers are safe to use if you are using them correctly. It’s important to make sure they are clean, especially any seals or valves. Check the valves work before use, and don’t overheat.

If you do this, you shouldn’t have any problems.

Final Thoughts

Pressure cookers are often thought to reduce food’s flavor since you add water, but after giving it a try, you’ll find that’s not true. The steam it creates is to cook the food quickly, not to take away the taste.

Even though the pressure cooker uses steam and water, it still can brown and caramelize your food, which gives it added flavor compared to traditionally steamed foods, which usually taste bland.

Now that you know all about how pressure cookers can revolutionize your kitchen experience, find the best model for your needs. You can also find tons of delicious recipes to try!