Since around 2010 a new craze hit the world of cooking referred to as instant pot (or IP) cooking. It is basically any electric pressure cooker with extra safety features that old style pressure cookers lack as well as having other cooking options so that it can function as a crockpot, steamer, or used like a Dutch oven would be on the stove top to brown, simmer, or warm. Instant Pot was/is a brand but like the Hamburger Helper brand has become a generically used and common household phrase used to describe all things similar to it.
There are many claims about how much faster and easier it is to use over convential cooking methods. In particular are claims that it is the healthier cooking method and preserves more nutrients due to shorter cooking times.
First of all, the concept of preserving food nutrients from a scientific stand point is pretty simple. The more you peel, cut, or cook something the more nutrients are lost.
Although there are exceptions — such as garlic for example which is actually more nutritious if cut and allowed to sit for ten minutes or so.
The smaller you cut something up the more it is exposed to evaporation principles which takes with it nutrients. Peeling removes both nutrients (usually the peel is actually the best source of nutrients) and fiber. Any juices that escape during the cutting process also take nutrients with them.
The longer something cooks the more nutrients are leached out or in some instances denatured or destroyed. A generally well known fact and the one most IP promoters push as being the reason that IP cooking is better.
However, exposure to a much higher heat source does exactly the same thing but in even less time. The higher the pressure — the higher the heat. Temperature matters just as much as the legnth of time something is cooked. The higher the temperature the more nutrients that will be lost while cooler temperatures preserve nutrients.
This is particularly true of most vegetables. The softer or squishier the vegetable is the less nutricioius it will be. Vegetables should be tender but still have some crunch if cooked and otherwise should be eaten raw for maximum nutritional benefit. So unless you are cooking them into a soup or stew in which all of the liquid is being consumed then you really aren’t getting as many nutrients as compared to, say, oven roasting them or eating them raw.
According to the Journal of Food Science, a study in 2009 showed that baking, microwaving, and stir frying many vegetables actually increases their anti-oxidant activity — unlike any other cooking method including cooking under pressure.
Also, the more water used means that more nutrients will be leached from the food, however, the nutrients aren’t so much lost as simply transferred from the food into the water. If you are disposing the water then you are also disposing vital nutrients. Consume the water and you are consuming the leached nutrients. It is, then, simply a matter of how much of that water will or won’t be lost to evaporation.
If you cook an item under pressure then you must add water (or a sauce which is mostly water), therefore, you have to ask yourself if water would even be added at all if it were being cooked by another method.
On the other hand, if the water is going to be consumed and not discarded then cooking under pressure does help avoid evaporation keeping all the liquid inside the cooking vessel — well, while it is actually cooking anyway — so not really.
In fact, you actually lose MORE steam to the atmosphere during venting and when popping open the lid on a pressure cooker or an instant pot than what is lost by any other cooking methods — particularly when doing a manual venting rather than natural venting. At least with a natural venting some (though not all) of the steam is able through the condensation process to return to pot — rather than escape as steam carrying with it even more vital nutrients than all those other cooking methods.
You can decrease loss on the stove top, however, by simply putting a lid on your pot or pan. You lose just as much nutrients to the steam released into the atmosphere when opening the lid on a crockpot as you do when removing the lid on a regular pot or pan. And these release less steam having not been cooked under pressure in spite of longer cooking times.
And the whole process behind pressure cooking is centered around building up pressure, which converts water to steam, and creates higher temperatures. Otherwise, it wouldn’t be able to cook so quickly. And then the steam must escape to release all of that pressure taking with it all the nutrients which leached out into it.
The focus, as always, being on speed, everyone is looking for that magical item or gadget that is going to speed up and revolutionize the whole process of cooking foods. Well, pressure cooking as a means of speed cooking has been around for a very long time so really isn’t a new concept at all and scientifically speaking the process works no differently in an electric pressure cooker than it does in the old style pressure cookers. You just have a few other non-pressure cooking options and preset buttons to avoid having to watch a pressure guage now, a clock, and a single beep to let you know when the cook cycle finishes so you can choose which vent method to use.
Many, if not most, IP cookers (and bakers, and cooks, etc.) like to use frozen or canned fruits rather than be bothered with preparing fresh fruit.
Freezing preserves much of the nutrients although there is about a 30 percent loss of Vitamin C content, so fresh is still best with Vitamin C containing produce, but freezing isn’t going to break the nutritional bank. However, the majority of frozen fruits purchased from the grocery freezer section have been peeled prior to freezing as well as already cut up.
Canned fruits need only to be reheated (and not even that really) rather than actually cooked. Cooking rather than simply reheating already canned fruits is going to further destroy additional nutrients. They’ve already been cooked once and it isn’t nutritionally sound to cook them yet again. If planning to cook fruit then fresh fruits are the better choice nutritionally. Better still is to simply eat them raw.
Some claim that an IP is the only cooking device you’ll ever need. However, like any other kitchen appliance it is just not for everything. And just like pressure cookers of old you need to be cautious and do proper maintenance and check the seals, etc. before every use. And ask yourself if you would rather trust an electronic indicator to tell you if something is wrong — because those can break down just like any other mechanical or electrical appliance — or keep check on things yourself. Lids are better designed (supposedly) than pressure cookers were before for safety and ease of use. They are definitely easier to put on and take off. However, if you fail to maintain your device properly it too can explode just like its predecessors. Read your user manual — especially the safety instructions — about how to care for your device very carefully.
Does it cook faster? Well, the actual cooking part is quicker. However, you also have the time for the pressure to build up and after cooking the time needed to vent and depressurize.
It takes ten to forty minutes on average, depending upon the size of the IP and the quantity and density of the food inside, just for the pot to build up pressure before any actual cooking starts. Sometimes this is offset by the shorter cook times and other times not.
Venting also takes a few minutes to five minutes for manual release and ten or more minutes for natural release. It depends upon size of the pot, the quantity and density of the food, how much liquid, how much pressure, how much and how long the heat, etc.
It takes only ten to thirty minutes total to prepare a home made (scratch) goulash or what some refer to these days as a hamburger helper on the stove top and you could be sitting down eating before the IP even finishes building up pressure.
Some like to prepare cakes in the IP. This involves preparing and filling several small ramekins, carefully tenting with foil to avoid water logging them in the IP during pressure cooking/steaming, and arranging and stacking them inside the pot. Many like to do this using over processed, artificial ingredient laden, boxed cake mixes because to them speed is far more important than health.
But are they really getting all that much more speed?
Again, time is needed to build up pressure before cooking actually starts. i can have a homemade cake from scratch mixed and put into a prepared cake pan and put into the oven before the instant pot is even switched on while they prepare all those ramekins, etc. — and by the time the IP has finished my scratch cake (with no artificial preservatives, colors, flavors, etc.) is already out of the oven and cooling.
Does this all mean that you should avoid IP cooking? Not at all. But a wise and nutritious cook doesn’t put all their eggs in just one basket. It is a tool like any other appliance and has a purpose. It just simply isn’t all the things it has been hyped up to be. For better health and nutrition the best method is to use a variety of cooking methods just as you want to eat a variety of foods. Using only one method of cooking is no healthier than choosing to eat only broccoli and eating no other vegetable.
That said, keep your eyes peeled for future postings here with more practical uses and recipes for IP/electric pressure cooking!
Here is one such example: