Abstract：Bioactive peptides can be defined as protein fragments with potential biological activities. Milk proteins are precursors of many different biologically active peptides. Bioactive peptides from milk proteins are considered potential modulators of various regulatory processes in the body.

They mediate physiological functions in cardiovascular, nervous, gastro intestinal and immune systems. The functional significance of bioactivities depends on peptide fragment. Bioactive peptides encrypted in major milk proteins are latent within the sequence of the parent protein molecule. They can be liberated by (i) gastro intestinal digestion of milk, (ii) fermentation of milk with proteolytic starter cultures, and (iii) hydrolysis by proteolytic enzymes. In relation to their mode of action, bioactive peptides may reach target sites at the luminal side of intestinal tract, or after absorption, in peripheral organs. The production, functionalities, and mode of action of bioactive milk peptides as well as latest peptide products and ingredients are reviewed.