This is the second part of a discussion comparing Induction Cooktops (IC) versus Multi-Function Electric Pressure Cookers (MEPC).
Power
Consumer ICs max out at 1,800W (15A at 120V) to 2,300W (10 A at 230V) and typically have 8-10 controllable levels. The lower levels may be on/off cycling of the lowest actual power level.
A 120V MEPC has a 1,000W heater that is cycled either on or off at full power. The lower power means that an IC will heat up any given quantity of water quicker than an MEPC.
Energy Efficiency
The two appliances are close in efficiency in straight boiling water tests, with the IC a few points higher in efficiency. But for pressure-cooking, the combination of pressure and insulation make the MEPC remarkably efficient. A recipe using three cups of rice plus a cup and a cup and a half of dry beans used only 0.5 kWh, while the same general recipe took almost 0.7 kWh on the IC, even though the beans had been soaked overnight.
An IC has multiple cooking levels. In general, it will boil food at atmospheric pressure which means a maximum cooking temperature of 212F/100C. However, it can get a frying pan up to an extremely high temperature (460F/238C). It has a cooking surface temperature sensor which will shut the unit off if the surface gets too hot.
One advantage of the MEPC is the pressure-cooking function. For foods that respond well to pressure cooking, the IP cooks at 10.5 to 11.6 pounds per square inch, which translates roughly to 240 degrees F. This is higher than boiling, but not as high as typical baking. However, pressure cooking, combined with the insulated casing, means the MEPC uses remarkably little energy to cook things like rice or beans, or to cook stews made of tougher pieces of meat.
Cooking Time
The IC has higher power, so it will bring a given quantity of water to boiling faster than an IP, and it can provide a hotter surface for frying/sautéing. Cooking white rice on an IC involves bringing the rice and water to a boil at high power (ten minutes or so) then putting a lid on and cooking at low power for an additional ten minutes.
However, the pressure-cooking function of the MEPC means that dishes such as beans will cook much faster. The MEPC will also be quicker for meat stews, especially those made from tougher cuts. Typical pressure cooking on the MEPC requires a “heat up time” (to bring the water in the pot up to pressure – 10-20 minutes), then the “cooking time” (as little as 4 minutes for white rice, longer for beans, stews and other foods), then some time to release pressure. Many recipes call for “natural release” which means that the pressure reduces naturally as the pot cools (and leaks a little?). This is typically 15 to 20 minutes. Quick release can be achieved by twisting the pressure release valve, which releases the superheated steam into the air (this is very dramatic, somewhat messy, and quite dangerous, but it takes less than a minute). As an example, cooking dried beans takes about an hour – 20 minutes to get to pressure, 22 minutes timed cooking and 18-20 minutes for natural pressure release.