Lupin protein-stabilized oil droplets contribute to structuring whey protein emulsion-filled gels

TY - JOUR

T1 - Lupin protein-stabilized oil droplets contribute to structuring whey protein emulsion-filled gels

AU - Grasberger, Katherine Findlay

AU - Hammershøj, Marianne

AU - Corredig, Milena

PY - 2024/2

Y1 - 2024/2

N2 - This work aimed to understand the role of lupin protein or mixed lupin-whey protein stabilized oil droplets on the texture and microstructure of a heat-induced whey protein gel. Protein-stabilized emulsions were compared to surfactant-stabilized emulsions to investigate the potential of their interfacial interactions to impart unique structures in the filled gels. The structure development was followed in situ using rheology and the final heat-induced gels were characterized by small and large amplitude oscillatory rheology and confocal microscopy. The development of the gel modulus as well as the final gel properties were linked to the type of interactions between the whey protein matrix and the protein adsorbed at the oil interface. The final gels were selectively dissolved in various buffers, and the results showed that replacing interfacial whey protein with lupin protein resulted in a reduced amount of disulfide bridges, explaining the softer gel in the lupin containing gels compared to those with whey protein. Non-covalent interactions were the main forces involved in the formation of actively filled droplets in the gel network. This work demonstrated that by modulating the interfacial composition of the oil droplets, differing gel structures could be achieved due to differences in the protein–protein interactions between the continuous and the interfacial phase. There is therefore potential for the development of innovative products using lupin-whey protein mixtures, by careful control of the processing steps and the matrix composition.

AB - This work aimed to understand the role of lupin protein or mixed lupin-whey protein stabilized oil droplets on the texture and microstructure of a heat-induced whey protein gel. Protein-stabilized emulsions were compared to surfactant-stabilized emulsions to investigate the potential of their interfacial interactions to impart unique structures in the filled gels. The structure development was followed in situ using rheology and the final heat-induced gels were characterized by small and large amplitude oscillatory rheology and confocal microscopy. The development of the gel modulus as well as the final gel properties were linked to the type of interactions between the whey protein matrix and the protein adsorbed at the oil interface. The final gels were selectively dissolved in various buffers, and the results showed that replacing interfacial whey protein with lupin protein resulted in a reduced amount of disulfide bridges, explaining the softer gel in the lupin containing gels compared to those with whey protein. Non-covalent interactions were the main forces involved in the formation of actively filled droplets in the gel network. This work demonstrated that by modulating the interfacial composition of the oil droplets, differing gel structures could be achieved due to differences in the protein–protein interactions between the continuous and the interfacial phase. There is therefore potential for the development of innovative products using lupin-whey protein mixtures, by careful control of the processing steps and the matrix composition.

KW - Emulsion-filled gels

KW - Lupin protein

KW - Plant-dairy protein mixtures

KW - Rheology

KW - Whey protein

UR - http://www.scopus.com/inward/record.url?scp=85182267159&partnerID=8YFLogxK

U2 - 10.1016/j.foodres.2024.113987

DO - 10.1016/j.foodres.2024.113987

M3 - Journal article

C2 - 38309923

SN - 0963-9969

VL - 178

JO - Food Research International

JF - Food Research International

M1 - 113987

ER -