Peptides are molecules built from two or more amino acids joined by peptide bonds, spanning dipeptides, oligopeptides, and long polypeptides. In foods they influence taste, texture, and nutrition: some taste bitter or savory, others act as antioxidants or blood-pressure-lowering agents, and digestion plus fermentation continuously creates them during ripening and processing. Bioactive peptides attract growing interest as functional ingredients that may support cardiovascular or immune health. In manufacturing, proteolysis is steered through enzyme choice, cultures, and conditions to shape the peptide mix. Analyzing peptides helps developers optimize flavor, functionality, and health properties of protein-rich foods.