1. Introduction
Traditionally, protein in the diet has been considered mainly as a source of essential amino acids for cellular maintenance, growth and energy. More recently, dietary proteins have been recognised additionally for their bioactive properties once hydrolysed by proteases in the gastrointestinal tract following consumption. Bioactive peptides are defined as being short amino acid sequences that possess one or more biologically significant activities when taken up into the body (Fitzgerald et al., 2004 and Lafarga and Hayes, 2014).