Effects of processing on the infant digestion of goat milk proteins: from proteolysis, peptides formation, to peptides absorption.

Goat milk-based IF was approved as a legal commercial product in the European market in 2012. As a relatively new type of IF, the research on goat milk-based IF is limited and not enough to support that IF from different sources should share a similar standard to achieve better digestibility. This thesis focuses on the infant digestion of proteins in goat milk, which displays different protein composition and digestion properties from cow milk. It is necessary to treat goat milk as an individual type of milk to develop its own formulation for infant nutrition and health. Apart from the formulation, processing is necessary for goat milk-based IF to ensure the safety and quality of the products. However, the processing steps induce the structural changes of proteins which further impact their proteolysis, peptides formation, and absorption during gastrointestinal digestion. The aim of this thesis is to compare two formulations of goat milk with different casein:whey protein ratios. Meanwhile, different types of heating and homogenization were achieved to study the effects of processing on the digestion of proteins. Additionally, the study considered lipid addition and structure. This thesis underscored the distinct reactions of caseins and whey proteins during heating, proteolysis, protein cleavage and absorption of peptides.