The health-improving effects of biologically active peptides are well known due to their positive influences on physiological systems such as the gastrointestinal, immune and nervous systems. These peptides are specific amino acid sequences that remain inactive when they are part of the parent polypeptide chain but become active once they are released by proteolytic enzymes. Bioactive peptides can be found in protein hydrolysates, fermented foods and also during the enzymatic digestion of proteins in the human gastrointestinal tract.
In order for these peptides to exert their beneficial effects they must resist gastrointestinal enzymatic degradation, first by pepsin and then by chymotrypsin and corolase PP (a mixture of the three major pancreatic enzymes). They must also be resistant against degradation by cytosolic and plasma proteases. These requirements can be met if the peptides are produced in a suitable manner.
Many bioactive peptides are bitter and therefore unpalatable, a factor that limits their widespread use in functional foods, supplements and drugs intended for oral administration. To address this problem, a number of strategies to make these peptides more palatable have been developed. These include debittering, masking and modulation techniques as well as encapsulation technologies. This article, which is part of a special issue on ‘Bioactive Peptides: Processing and Applications’ of the journal Food Production, Processing and Nutrition, presents an overview of these approaches and their current application to produce peptides with improved palatability. The articles presented in this collection include new research and comprehensive reviews that report current developments within the field of peptide palatability.