Our aim is to gain knowledge of the effect of processing on the biochemical and physicochemical properties of proteins in raw materials, ingredients and foods, in relation to their functional and nutritional properties Since proteins vary widely in their structure, their functional properties will diverge accordingly. Additional factors of influence for the functionality of proteins are isolation procedure, (physico-)chemical or enzymatic modification, and the composition and processing route of the food in which they are applied. Knowledge of structure-function relationships of proteins in foods, and the interaction between proteins and other food constituents form the basis for the development of modern processes, of new ingredients and of higher quality products.
Description of theme
In the group there are four major research lines.
1) Novel and current plant proteins (including microalgae): Focussed at isolation methods and issues and characterization of the obtained concentrates/isolates.
2) Enzymatic hydrolysis of proteins: To describe the protein hydrolysis a method has been developed focussing on the identification and quantification of all peptides in hydrolysates taken during hydrolysis. This allowed further development of concepts to characterize this process and relevant molecular properties of both protease (selectivity) and substrate.
3) Maillard reactions: In order to understand the effects of Maillard reactions on ingredient functionality we need adequate methods to quantify the extent of modification. For this different methods are applied, improved and combined.
4) Foam- and emulsifying properties of proteins: We develop methods and concepts to describe the these properties in terms of their molecular properties.
Analytical methods used therefore range from those to determine protein conformation (CD), LC-MS, light-scattering and multiple chromatographic or electrophoretic techniques. Asymmetric flow-field flow fractionation coupled with a multi-angle light scattering detector is used for the characterisation of protein aggregates. Furthermore we have equipment to determine interfacial, foaming and emulsifying properties of proteins. This is supplemented with studies of thin liquid films studied under reflected light microscopy. To study in vitro hydrolysis we have several pH stat units. The study of proteins from several angles provides a complete overview.
- Current: Predictive estimation of emulsion and foam properties of plant protein mixtures
- Current: Understanding protein hydrolysis in vitro and in vitro
- 2018: Towards predicting enzymatic protein hydrolysis, Yuxi Deng MSc, dr.ir. Peter Wierenga, Prof. dr H.A. Schols, prof.dr.ir. H. Gruppen
- 2018: Unicellular protein: isolation, techno-functionality and digestibility, Emma Teuling MSc, dr.ir. Peter Wierenga, dr.ir. J. Schrama, prof.dr.ir. H. Gruppen
- 2017: Sugar beet leaves: from biorefinery to techno-functionality, dr.ir. Peter Wierenga, prof.dr.ir. H. Gruppen
- 2017: Protein digestion kinetics in pigs and poultry, Hsuan Chen MSc, dr.ir. Peter Wierenga, dr. A. Jansman, prof.dr.ir. W. Hendriks
- 2016: Foam properties of proteins, low molecular weight surfactants and their complexes, Frederik Lech MSc, dr.ir. Peter Wierenga, dr. ir. Marcel Meinders, prof.dr.ir. H. Gruppen
- 2015: Modelling the peptide formation during fermentation of milk proteins - dr. Rafael Munoz-Tamayo, dr.ir. Peter Wierenga, prof.dr.ir. H. Gruppen, prof.dr.ir. M.A. Zwietering (Food Microbiology)
- 2015: Mesoscale structure and techno-functional properties of enzymatically cross-linked α-lactalbumin nanoparticles - Surender Dhayal MSc, dr.ir. Peter Wierenga, prof.dr.ir. H. Gruppen
- 2015: Correlating composition and functionality of soy protein hydrolysates used in animal cell cultures - Abishek Gupta MSc, dr.ir. Peter Wierenga, prof.dr.ir. H. Gruppen
- 2015: Maillard reaction products in pet foods, Lotte van Rooijen MSc, dr.ir. Peter Wierenga, dr. G. Bosch, prof.dr.ir. W. Hendriks
- 2014: Role of protein-protein interactions on protein aggregation and emulsion flocculation - Roy Delahaije MSc, dr.ir. Peter Wierenga, prof.dr.ir. H. Gruppen
- 2014: Introducing enzyme selectivity as a quantitative parameter to describe the effects of substrate concentration on protein hydrolysis - Claire Butre MSc, dr.ir. Peter Wierenga, prof.dr.ir. H. Gruppen
- 2013: Controlling the aggregation and gelation of β-lactoglobulin by the addition of its peptides - Hans Kosters MSc, dr.ir. Peter Wierenga, prof.dr.ir. H. Gruppen
- 2013: Physico-chemical and techno-functional properties of proteins isolated from the green microalgae Tetraselmis sp.- Anja Schwenzfeier MSc, dr.ir. Peter Wierenga, dr.ir. Marian Vermue (Bioprocess Engineering), prof.dr.ir. H. Gruppen
- 2010: Peroxidase-mediated cross-linking of bovine α-lactalbumin – Walter Heijnis MSc, dr.ir. Peter Wierenga, prof.dr.ir. H. Gruppen