What makes a popcorn bag inflate

Use a microwave-safe glass bowl and empty the kernels into it. Cover the bowl with a microwave-safe cover or dish preferably ceramic, but the microwave-safe part is the most important. If you want to get real fancy, you can purchase a microwave-safe food cover that has little vents in it.

That way, you won't have too much steam build up in the bowl. The heat from the popping kernels will create moisture in the covered bowl, and you'll get a glorious bowl of fluffy white popcorn.

Be sure to use oven mitts or a dishtowel when taking it out—the bowl and plate will be hot and steamy! You can also add a little oil, butter, and salt at the bottom of the bowl before you pour in the kernels. That way, the popcorn can soak up the flavor while it cooks. If you want your popcorn to taste more like movie popcorn, use oil and some Flavacol.

Another nice thing about this method is that if there are any un-popped kernels remaining, you can return them to the microwave and they'll cook on the next go-round. Keep in mind that if you favor the covered bowl method which I do , you can buy popcorn kernels in bulk in lieu of microwave bags, thus saving a little dough.

After all, farmers don't grow special "microwave only" corn. Finally, if you have an iPhone, there's an app called Perfect Pop that lets you know when your microwave popcorn is ready. Just turn the app on and leave the phone near your microwave. A "kernel widget" analyzes the sound of popping corn weighed against information gathered from several types of microwaves as well as different types of microwave popcorn. When everything sounds right, the app lets you know that it's time to stop poppin' and time to start noshin'.

Popcorn pops because each popcorn kernel is special. Here's a look at what makes popcorn different from other seeds and how popcorn pops. Popcorn kernels contain oil and water with starch, surrounded by a hard and strong outer coating.

When popcorn is heated, the water inside the kernel tries to expand into steam, but it cannot escape through the seed coat the popcorn hull or pericarp. The hot oil and steam gelatinizes the starch inside the popcorn kernel, making it softer and more pliable.

When the popcorn reaches a temperature of C F , the pressure inside the kernel is around psi kPa , which is sufficient pressure to rupture the popcorn hull, essentially turning the kernel inside-out.

The pressure inside the kernel is released very quickly, expanding the proteins and starch inside the popcorn kernel into a foam , which cools and sets into the familiar popcorn puff.

A popped piece of corn is about 20 to 50 times larger than the original kernel. If popcorn is heated too slowly, it won't pop because steam leaks out of the tender tip of the kernel. If popcorn is heated too quickly, it will pop, but the center of each kernel will be hard because the starch hasn't had time to gelatinize and form a foam. Originally, popcorn was made by directly heating the kernels.

Bags of microwave popcorn are a bit different because the energy comes from microwaves rather than infrared radiation. The energy from the microwaves makes the water molecules in each kernel move faster, exerting more pressure on the hull until the kernel explodes.

The bag that microwave popcorn comes in helps trap the steam and moisture so the corn can pop more quickly. Each bag is lined with flavors so when a kernel pops, it strikes the side of the bag and gets coated. Some microwave popcorn presents a health risk not encountered with regular popcorn because the flavorings are also affected by the microwave and get into the air.

Popcorn that you buy at the store or grow as popcorn for a garden is a special variety of corn. The commonly cultivated strain is Zea mays everta , which is a type of flint corn. Some wild or heritage strains of corn will also pop. The most common types of popcorn have white or yellow pearl-type kernels, although white, yellow, mauve, red, purple, and variegated colors are available in both pearl and rice shapes.

Freshly harvested corn pops, but the resulting popcorn will be chewy and dense. Heat up that kernel, and the water molecules locked inside will expand until the pressure and heat cause the starch to inflate and explode, bursting the hull and turning the kernel inside-out.

What you have left after this popping occurs is a filling, low-calorie, whole-grain food packed with fiber. Along with fiber, popcorn is a source of polyphenols—a type of plant antioxidant linked to improved cell health. Most fruits and vegetables are mainly water—meaning you have to eat a relatively large portion of them to get meaningful amounts of their healthful nutrients, Vinson says. Popcorn is a much more condensed source of antioxidants. But while popcorn in its natural state is a snack you can feel good about, how you prepare it can lessen its healthful properties.

Research has linked the coatings used in microwave popcorn to health issues. Reports from the Environmental Working Group and others have also revealed that some chemicals used to coat microwave popcorn bags and keep the oils inside from leaching through are likely carcinogens.

Those reports led the FDA to ban some of these chemicals from popcorn bags and other consumer goods. While those health concerns associated with pre-bagged microwave popcorn are not definitive, other prep methods are probably safer choices, Taylor says.

But even if you heat popcorn kernels in a stovetop crank-style popper, experts say there are some reasons to be wary. Some people add oil to their naked corn kernels in order to encourage rapid heating. But many oils will burn and smoke before the popcorn has popped. How bad this burned oil is for you depends on how often you consume it.