Why is pepsin not produced straight away(without the presence of food)?

Pepsin is not produced immediately because it is secreted as an inactive precursor called pepsinogen, which protects the gastric mucosa from being digested by its own enzyme. The production of pepsinogen is stimulated by the presence of food in the stomach, along with hormonal signals. This mechanism ensures that pepsin is activated only when needed, preventing premature digestion of stomach lining and reducing potential damage to the gastrointestinal tract.