The ability to store energy in pea protein gels is set by network dimensions smaller than 50 nm

• Fine and coarse stranded networks were obtained from pea proteins.
• Fine-stranded networks were formed at a pH away from IEP and at low ionic strength.
• Coarse networks were formed at a pH close to IEP and at high ionic strength.
• The ability of the networks to elastically store energy was related to the microstructure.
• Elastically stored (recoverable) energy is set on length scales smaller than 50 nm.
• Elastically stored energy can be modulated via creation of different network structures.

The objective of this study was to identify which length scales set the ability to elastically store energy in pea protein network structures. Various network structures were obtained from pea proteins by varying the pH and salt conditions during gel formation. The coarseness of the network structure was visualized by the use of confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) and ranked from least coarse to most coarse networks. Least coarse networks were formed at a pH away from the isoelectric point (IEP) of pea proteins, and at a low ionic strength, whereas more coarse networks were formed at pH values close to the IEP and at a high ionic strength during gel formation. Mechanical deformation properties of the gels such as elastically stored (recoverable) energy, Young's moduli (stiffness of gels), fracture stress (gel strength), and fracture strain (brittleness of the gels) were measured by the use of a texture analyzer and correlated to the coarseness of the networks structure. The influence of coarseness on the ability of the networks to elastically store energy was observed for length scales below 50 nm. The findings show that elastically stored energy of pea protein gels can be modulated via the creation of different network structures below 50 nm length scales. The results from this study contribute to a better understanding of the dimensions that set the ability to elastically storage in pea protein gels. If the ability of pea proteins to store energy can be understood, products can be better tailored for consumers.