Enzymatic Hydrolysis Of Protein Isolate From Mussel Powder (Mytiluscoruscus): Kenitic, Characterisation, And Peptides Functionality

A growing body of scientific evidence in the past decade has revealed that many food proteins and peptides exhibit specific biological activities in addition to their established nutritional value. Bioactive peptides have been found in enzymatic protein hydrolysates and fermented dairy products, but they can also be released during gastrointestinal digestion of proteins. Many studies have demonstrated that mussel protein have potent antioxidant activity. Isolated from gastrointestinal digest.This thesis made it possible to study obtaining protein content, functional properties or biologically active peptides with through the development of processes for the preparation and the hydrolysis of protein isolates resulting from mussel powder.First, a method of preparation of protein isolates being different by the type of proteins was developed. The isolates do not have good functional properties but their partial hydrolysis by Alcalase 2.4L improves some of them. Then, the hydrolytic action of commercial proteases (Alcalase 2.4L, Pronase SG, Neutrase 0.8L, Lypaine 6500) on the isolate of different process were compared. It was shown that the kinetics of hydrolysis is significantly influenced by the specificity of the enzyme and there is a relation enzyme/degree of hydrolysis (DH)/targeted activity. Lastly, we showed for three different enzyme/substrate systems that at given DH and pH, the composition of the hydrolysates is independent of the initial enzyme and substrate concentrations and of the temperature.Thus, the prediction of the temporal evolution of the DH, whatever the values of precedent parameters, allows to control the generation of a peptide mixture with targeted properties. A model based on the reaction pathway of Michaelis-Menten was then built in order to simulate the hydrolysis kinetics in batch reactor. For that, limiting phenomena implied in the hydrolysis (inhibition or inactivation of the enzyme, modification of the substrate) were highlighted.