Cheese was likely discovered by accident over 4,000 years ago when an Arabian traveler's milk curdled during a desert journey.

Archaeological evidence suggests that cheese-making dates back to at least 5500 BCE in Kujawy, Poland, where perforated pottery shards containing milk fat residues were discovered. However, the popular legend of the Arabian traveler provides a practical explanation for how the process was first observed. The sheep stomach used as a flask contained rennet, a complex of enzymes including chymosin, which is still used in modern cheese production to coagulate milk.The combination of the warm desert sun and the rhythmic swaying of the traveler's camel provided the perfect conditions for the rennet to react with the milk. This chemical reaction breaks down the kappa-casein proteins that keep milk in liquid form, causing the solids to clump together into curds. The remaining liquid, known as whey, provided a refreshing drink, while the solid curds offered a portable and durable source of protein.By the time of the Roman Empire, cheese-making had become a sophisticated art with hundreds of varieties documented by scholars like Pliny the Elder. In his 77 AD encyclopedia, Naturalis Historia, Pliny noted that cheese was a staple food for many civilizations. This transition from an accidental discovery to a dietary staple allowed ancient populations to store surplus milk and survive during seasons when fresh food was scarce.