Pressure Cooking

From CopperWiki

Pressure cooking is a technique whereby food is cooked in a sealed vessel that does not permit air or liquids to escape below a preset pressure. Under pressure, water’s boiling point increases and raises above boiling point. This helps cook the food thoroughly and faster.

[edit] History

In India, the technique of mild pressure cooking goes back to the 18th century to Awadh in the northern state of Uttar Pradesh. It was here that a technique called dum was perfected. It involves placing food in large clay pots and tightly sealing their tops with dough to prevent steam from escaping. The technique literally chokes off the steam and allows food to cook gently in its own juices, with the steam infusing flavours and preserving the nutrients. [1]

Pressure cooking as we know it today is done in a unique vessel invented by Denis Papin, a French physicist, in 1679. The first pressure cooker patent was granted in 1902 in the US. Pressure cookers became popular in 1939 when they were commercialised by National Presto Industries. [2]

[edit] How Pressure Cooking Works?

A pressure cooker seals steam inside; this steam builds pressure inside the cooker and raises cooking temperatures to significantly higher levels than those under normal conditions. At 15 lbs. pressure, for example, the temperature inside a pressure cooker can reach 250°F.

The super-heated steam results in high-speed cooking, which is typically three to 10 times faster than other conventional methods. The pressure cooker is designed in a manner that when sufficient pressure is built, it also releases the steam.

Pressure cooking is ideal for cooking meats and poultry, vegetable, lentils, cereals and even rice.

[edit] Some Tips

Pressure cooking is fairly simple, but a few important tips ensure that food is cooked appropriately:

Read the recipe before pressure cooking.

It is okay to use more liquid than recommended but never less.

Make sure that the cooker’s lid is properly closed and locked into position before developing pressure. The gasket or rubber should be in place.

Make sure that the pressure release mechanism is not clogged before using it.

Bring the recipe to the boil before closing the lid to facilitate faster pressurization.

Timing is important when pressure is being built up, so keep an eye on the watch, or better still, keep a timer handy.

Food that is cut uniformly will cook evenly. When mixing foods, cut those that cook more quickly into larger pieces and those that cook slowly into smaller pieces.

If your recipe calls for sautéing, browning or searing, scrape up the brown bits that stick to the bottom so they are loose when you add the liquid. This will prevent the food stuck the bottom from burning.

If you open the cooker and find too much water, just cook it uncovered till the liquid is reduced.

Pre-soak food that absorbs liquids, such as dried beans, cereals, lentils, split peas, rice, etc. This will hasten the cooking and less water will be required while pressure cooking.

Once you have reduced pressure, take the cooker off the fire and let the pressure drop to normal before opening it.

[edit] Is It Healthy?

Pressure cooking retains more nutrients than other cooking methods as vitamins, minerals and other nutrients aren’t boiled away during cooking. You can choose to use little or no fat as pressure cooking steams food. By using a cooking rack in the pressure cooker, it is also possible to keep foods out of the cooking liquid and let the fat in foods drain away.

[edit] Is It Energy Efficient?

Not only is it a simple cooking technique, the build-up of steam in the cooker hastens cooking, making it is one of the most energy-efficient cooking techniques. Compared with conventional cooking techniques, most foods cook 70 per cent faster when pressure cooked. It takes even less energy than microwave cooking.