Why Some Types Of Food Fare Better In The Microwave
Microwaves do not treat all foods equally. Grapes, for example, explode, as seen in a YouTube video The New York Times shared. According to Kitchen Gearoid, this is because if you cut a grape in half and place those halves together, microwaves will jump between the halves creating an electromagnetic field that will catch fire.
Grapes, like hard-boiled eggs, belong to a small selection of foods that can explode in the microwave. However, the effect microwaves have varies between different types of food. The reason is due to how microwave ovens work. The World Health Organization (WHO) explains that the microwave oven emits microwaves thanks to a magnetron. These microwaves reflect off the oven's walls and are absorbed by the food. Once absorbed, the waters and oils in the food will vibrate, the resulting friction of which will heat the food. Note that it is the food itself that is heating, not the air around it. Since it is the food that's heating, the composition of the food determines how it reacts to the microwaves.
Fatty foods are the best to microwave
The composition of fatty foods lends itself better to microwaves than non-fatty ones. The Kitchn explains that this is not because of the water content. Typically, foods with high water content cook quicker because they are better at absorbing microwaves. But the oils of fatty foods have a lower heat capacity than water, so it heats quicker. That said, if you find your fatty foods are overcooking in the microwave oven, Kitchen Snitches suggests putting a microwave-safe mug of water in the microwaves as well as the extra water will absorb more of the microwaves, thus slowing the cooking process.
Carbs and proteins also react in their own way to microwaves. Merck Manual explains that proteins are molecules with fundamentally complex structures while carbohydrates can come either as simple molecules or a complex structure of those simple molecules. The higher complexity of proteins is why meat cooks so much slower than carb-heavy foods like pasta or better yet French fries.