Historically, milk was stored in sacks made from animal stomachs and as it was exposed to environmental conditions, it soured, leaving behind milk solids or curds and a thin liquid called whey. It didn't take long to figure out that milk could be more easily preserved in the form of cheese. It was also soon discovered that rennet, an enzyme found in the stomachs of milk-producing animals, was actually the coagulant that caused curds to form. Cheese-making soon became an art and a profession as different textures, tastes and aromas came into play.
