Refrigerator

food storage · invention · cold · everyday science

Keeps food fresh. A refrigerator cools food to between 3 and 5 degrees Celsius (about 37-41°F), which slows down bacteria growth and keeps your food from spoiling quickly.

Heat pump magic. Instead of making cold, a refrigerator actually moves heat from inside the box to outside your kitchen, kind of like pushing warmth out the door.

Replaced the icebox. Before modern fridges, families used iceboxes, which were boxes filled with actual ice blocks that melted slowly to keep food cold for about 150 years.

Freezer below zero. A freezer is the coldest part of a refrigerator, kept at −18°C (0°F), which freezes water solid and keeps food fresh for much longer than the regular fridge section.

Stops bacteria growth. Bacteria that spoil food multiply much more slowly in cold temperatures, so your leftovers and fresh ingredients last way longer in a fridge.