It takes about 10 pounds of milk to make just 1 pound of hard cheese.

Milk contains tiny protein bubbles called casein micelles. When makers add an acid or an enzyme called rennet, these bubbles collapse and stick to each other. This process traps fats and minerals like calcium inside a solid structure.The history of cheese goes back a long time. Archaeologists in Poland found pottery strainers with milk fat on them from around 5,500 BCE. In 2018, researchers also found a piece of solid cheese in an Egyptian tomb that was 3,200 years old.Most of the liquid in milk is water, which is why so much milk is needed for a small amount of cheese. During aging, helpful bacteria like Lactobacillus eat the milk sugars. They turn the sugars into lactic acid, which helps keep the cheese from spoiling.The different flavors and textures of cheese come from how long it sits and which bacteria are added. Some cheeses age for only a few weeks, while others age for several years. This ripening process changes the chemical makeup of the cheese over time.