Probing Question: How do microwaves cook food? | Penn State University

Think about it—most of us do n’t go through an stallion day without using a microwave oven. But how does it work ? What actually happens when you “ nuke ” yesterday ‘s pizza or pop a bag of popcorn in the microwave ? And does the term “ nuke ” base there ‘s in truth radiation inside that box ?
“ Although technically microwaves are a kind of electromagnetic radiation, we should n’t use the word ‘radiation ‘ to describe them—it scares a batch of people unnecessarily, ” says Swamy Anantheswaran, Penn State professor of food skill. “ actually, microwave ovens operate in the electromagnetic spectrum at about the lapp frequency as a set of telephones—2450 megahertz, ” he adds. “ But they have more power output as compared to cell phones. That ‘s why the FCC tightly regulates their manufacture. They want to make sure they ‘re built good enough to contain all of the radio receiver emissions. ”
microwave Emily Wiley
therefore, microwaves are fair high-frequency electromagnetic waves, and your microwave oven creates a high-intensity electromagnetic sphere to cook your food. But what are those waves actually doing in there ?

Microwaves do most of their work on the urine in food, Anantheswaran says. “ Water molecules constitute what are known as ‘dipoles, ” he explains. “ A dipole is sort of like a bar attraction, with a positivist pole and a damaging perch. The oven ‘s electromagnetic field oscillates as it passes through the water molecules in the food, changing the mutual opposition of the field and causing the dipole/water molecules to flip themselves in order to be aligned with the new mutual opposition. ” Heat is created by the resulting clash of the water molecules reversing management millions of times a second .
conventional ovens trust on conduction to slowly spread the heat from the outside of the food to the inside ; by the time the inside is cooked, the outdoor may be over-cooked. In microwave cook, the energy reaches everywhere about at once, resulting in more-or-less even heating. “ It ‘s like each water molecule is a little heater heating the food, ” Anantheswaran says .
While protein, fatness, and starch molecules besides absorb microwave energy to a lesser degree, the presence of salt in foods can have a large determine on microwave heating. “ Salt molecules tend to break apart in the presence of water, ” notes Anantheswaran. The sodium and chlorine ions create heat by colliding in the quickly oscillate electromagnetic playing field, leaving less microwave energy available to heat the kernel of the food.

“ When you place a refrigerate bowl of soup in the microwave, ” he explains, “ the soup near the outside encounters the microwave energy beginning and very quickly heats. It even appears to be boiling. So you take the soup out—but then discover the central parcel is silent cold ” .
“ This is because the strategic arms limitation talks ions absorb so a lot energy around the outside of the bowl that they produce set boiling before the rest of the soup absorbs enough energy. ”
Microwave ovens can be big time-savers, Anantheswaran says. “ total cook time can be much less, allowing for greater retentiveness of nutrients. however, most consumers manage to overcook their food by leaving it in the microwave excessively long or by using besides high of a world power fix. ”

The solution is simple, he says, and as significant for base hit as for dependable eat .
“ Use the allow exponent setting for the food you ‘re microwaving, ” reminds Anantheswaran, “ and make certain you read the manual ! ”
Ramaswamy C. Anantheswaran, Ph.D., is professor of food science and graduate course of study coordinator. He can be reached at rca3 @ psu.edu .