Bioactive Peptides From Fermented Dairy Products: Production Methods and Functional Claims

Abstract

Fermented milks and cheeses are often described as sources of bioactive peptides, short protein fragments that, in laboratory tests, can inhibit angiotensin-converting enzyme, bind minerals, scavenge radicals or modulate immune cells. Such statements are attractive to producers and consumers, and they raise a practical question: how much of the claimed function is established for the products actually sold? This narrative mini review outlines how peptides arise during fermentation, ripening and enzymatic treatment, and how the choice of starter strain, substrate and process shapes what is released. It then examines the chain of inference that links a peptide sequence to a functional claim on a label. Much of the supporting evidence comes from in vitro assays and animal models, which say little about survival in the gut, absorption or effect in people. Human trials exist for a few casein-derived peptides and fermented milks, but they are generally modest in size, differ in product and population, and are hard to compare. Claims are only as strong as the weakest link in that chain. The review closes with the evidence a producer or regulator should expect before wording a claim, and it offers no advice to individuals.