What is rennet and starter culture?

Rennet is a natural enzyme derived from the stomach lining of ruminant animals, primarily used in cheesemaking to coagulate milk, helping it to form curds. Starter culture refers to specific strains of bacteria introduced to milk to ferment lactose into lactic acid, which aids in the development of flavor, texture, and acidity in cheese. Together, rennet and starter culture are essential for transforming liquid milk into solid cheese.