Why pressure cooker is used for rapid cooking?

Answer 1

To know how a pressure cooker works you must know the physics behind it. The boiling point of water is 100°C. When boiling with in a pot with no cap, no matter how much you heat, it will never go past the temperature of 100°C because of evaporation. Also the vaporized steam is the same temperature of the boiling water. So when you cook with a pot of water this time with a sealed cap, as you try to add more heat by increasing the temp., all that will happen is that the vapor will try to escape but because it is a sealed environment it will not be able to escape resulting in the build up of pressure (or force/area). The temperature and pressure will have a direct proportional relationship so as one increase so does the other. Also steam has 6 times the heat potential when it condenses (changes from gas to liquid state of matter) on a cold food product. The build up of pressure and heat potential are two factors which enable pressure cookers to cook foods faster and more efficiently.

In pressure cooker the pressure develops inside the vessel as time goes on. As pressure increases the boiling point of water also increases. Food inside the pressure cooker cooked very fast because of high boiling temperature, means the food is not cooked at 100 C but much higher temperature than 100 C.

Rapid S

Pressure cookers generally operate at 15psi (~760mmHg) above atmospheric pressure. Since atmospheric pressure is 14.7 psi, the pressure within the cooker is about double the atmospheric pressure. Once the operating pressure is attained, the temperature in the pot stabilizes at the boiling point for water at that pressure, which is about 120 C (248 F) at 2 atmospheres of pressure. Further temperature increase is prevented since the pressure is stabilized by the constant venting of steam from the cooking vessel.

If the temperature is raised by only 20 C above open pot boiling, why is the cooking time so much faster? The answer is that cooking results from chemical reactions in the food, and the rate at which all chemical reactions occur depends on the temperature. The temperature dependence of reactions is variable, but a rough rule of thumb is that the rate will double for every 10 C increase in temperature. Therefore the reactions that occur during cooking will occur roughly 4 times faster in a pressure cooker at 120 C, and the food will cook in one quarter of the time.

Answer 2

A pressure cooker works on the vaporization principle.

pressure builds up inside the cooker as the water inside it boils. it produces steam, which causes the temperature inside it to rise. the high temperature and pressure will result in a shorter cooking time

Added fact: boiling point of a liquid = the temperature at which the vapour pressure is equal to the pressure of the atmosphere above it. In a pressure cooker, the pressence of the steam increases the gas pressure above the water, thus elevating the cooking temperature and accelerating the cooking process.

Answer 3

It provides faster cooking of foods. The increased pressure and holding that higher pressure allows the water to rise to a higher temperature before biling out as steam thus cooking faster. The same principle is used in automobile radiators to pressurized them and allow higher water temperatures without boiling out the water as steam.

Answer 4

ADVANTAGES OF USING A PRESSURE COOKER:

1)Foods cook much faster with pressure cooking than with other methods. Due to the shorter cooking time, vitamins are preserved relatively well during pressure cooking.

2)Cooking food in pressure cookers requires much less water than conventional boiling, so food can be ready sooner.

3)Less energy is required than that of boiling, steaming, or oven cooking.

4)Pressure cookers can use much less liquid than the amount required for boiling or steaming in an ordinary saucepan.

5)Food is cooked at a temperature above the normal boiling point of water which kills most micro-organisms.

Answer 5

Pressure & Temperature in Pressure Cooker as compared to open cooking bowl ... Pressure cookers are used for cooking food faster than conventional cooking ..... much higher heat capacity, steam and liquids transfer heat more rapidly.

Best Electric Pressure Cooker

Answer 6

There are a few main uses for a pressure cooker canner. However, the main use is to can food. Canning food preserves it, and pressure cooking food cooks it, so pressure cooker canning cans cooked food.

Answer 7

There are a select few benefits to using a pressure cooker. The benefits to using this device are as follows: healthy, efficient, safe and versatile.