Master thesis defense by Rui Liu

The role of water in pea protein hydration/dehydration, denaturation, and degradation

To keep up with protein demand, new initiatives are required to increase the production of high quality, functional and sustainable proteins. One of these initiatives is the transition from animal proteins to more sustainable and cheaper plant derived proteins. Because compared with other legumes, pea protein not only has one of the lowest level of environmental
impact, but also it is non-genetically modified organism (GMO) and nonallergenic product, understanding of its functionality in order to make it applicable in food productions is needed. Since water molecules play an invaluable role in governing structure, stability, dynamics, and function of biomolecules, it is also important to know the role of water in pea protein hydration/dehydration, denaturation and degradation. With this in mind, we have used Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis coupled with Fourier Transform Infrared Spectroscopy and Mass Spectrometry (TGA-FTIR-MS), X-ray
Powder Diffraction (XRPD) and Optical Microscopy (OM) to characterize commercial pea protein isolate powder physical-chemical properties. From the results reported here we are able to demonstrate that time plays a crucial role on this protein physical-chemical properties and hypothesize that this observation is caused by water redistribution within the protein environment.