A pressure cooker is a large airtight pot that can be used on the stove top, on a campfire, or even in a microwave oven (specifically made for the microwave). The food is cooked with the pressure of steam. There are also electric pressure cookers that can be used anywhere there is an electrical outlet. Larger pressure cookers are used for canning, so make sure you know what you want to use the cooker for before buying it. The reason there has been such resurgence in pressure cooking is because they lock in the nutrients better than any other type of cooking. Pressure cooking retains 90 to 95% of the vitamins and minerals in food. Boiling retains 40 to 75%, roasting retains 53 to 90%, and steaming retains 75 to 90%.
Another reason for the renewed interest is because it is quick. You can come home at the end of a long day and prepare a meal that would sometimes take you all day.
It is a pretty simple concept of how the pressure cooker works. The pressure cooker generates steam by heating water or another form of liquid. Since the lid is tight the steam cannot escape so it produces pressure. Excess steam escapes through the vent. The pressure inside the pot maintains a constant internal pressure. The following video is a simple 3 minute demonstration that makes everything easy to understand:
If you want more information about temperature and psi, here are all the mathematical facts.
To further explain: psi stands for pounds per square inch. The regular stove top pressure cooker usually can go up to 15 psi. The average electric pressure cooker normally goes up to 11 psi. In conclusion, the stove top pressure cooker will cook slightly faster than the electric pressure cooker. All this means is that the average pressure cooker recipe is calculated for a 15 psi. So if you are using an electric pressure cooker you will need to add 5 to 10 minutes more of cooking time.
It is important that you understand that once the pressure level is reached that the recipe calls for, to turn the heat down. Leaving the heat on high does not make the food cook faster. This will only waste energy and use up all the liquid in the pressure cooker.
Here are 10 tips that everyone should review for pressure cooking. The very first time you use a pressure cooker may be a little intimidating, but after you do it one time you will be anxious to try it again because it is very easy. Just remember to read all the instructions in the manual and follow them. Pressure cookers differ from brand to brand and model to model so it is important that you are thoroughly familiar with your particular brand and model to get the best results possible.