TY - JOUR

T1 - Association of caseins with β-lactoglobulin influenced by temperature and calcium ions

T2 - A multi-parameter analysis

AU - Mohammad-Beigi, Hossein

AU - Wijaya, Wahyu

AU - Madsen, Mikkel

AU - Hayashi, Yuya

AU - Li, Ruifen

AU - Maria Rovers, Tijs Albert

AU - Jæger, Tanja Christine

AU - Buell, Alexander K.

AU - Hougaard, Anni Bygvrå

AU - Kirkensgaard, Jacob J.K.

AU - Westh, Peter

AU - Ipsen, Richard

AU - Svensson, Birte

N1 - Publisher Copyright: © 2022 The Authors

PY - 2023

Y1 - 2023

N2 - Aggregation of the major whey protein in bovine milk, β-lactoglobulin (β-Lg) is strongly influenced by association with caseins (CNs). Here, by using combined differential scanning fluorimetry and dynamic light scattering, the conformational stability and aggregation propensity of β-Lg and three types of CNs (α, β and ĸCNs) as well as their mixture have been systematically evaluated at different temperatures and Ca2+ concentrations in a multi-parametric approach. While β-Lg was affected significantly through denaturation and resulting aggregation by heat treatment with little dependency on Ca2+, αCN and βCN were influenced considerably by Ca2+. Through modifying the aggregation of β-Lg, CNs showed a different chaperone-like activity among the three types which were markedly dependent on the temperature and Ca2+ concentration. The presence of CNs resulted in smaller mixed aggregates compared to pure β-Lg aggregates, mainly through interaction of CNs with unfolded β-Lg and also by influencing the process of β-Lg unfolding. This was further confirmed by small angle X-ray scattering and isothermal titration calorimetry indicating that Ca2+ enhanced the interaction between β-Lg and CNs. Our experimental approach sheds light on molecular understanding of CN- β-Lg interactions and provides insight into how micro-structural assembly of milk proteins can be modulated to enable different functionalities in milk-based products.

AB - Aggregation of the major whey protein in bovine milk, β-lactoglobulin (β-Lg) is strongly influenced by association with caseins (CNs). Here, by using combined differential scanning fluorimetry and dynamic light scattering, the conformational stability and aggregation propensity of β-Lg and three types of CNs (α, β and ĸCNs) as well as their mixture have been systematically evaluated at different temperatures and Ca2+ concentrations in a multi-parametric approach. While β-Lg was affected significantly through denaturation and resulting aggregation by heat treatment with little dependency on Ca2+, αCN and βCN were influenced considerably by Ca2+. Through modifying the aggregation of β-Lg, CNs showed a different chaperone-like activity among the three types which were markedly dependent on the temperature and Ca2+ concentration. The presence of CNs resulted in smaller mixed aggregates compared to pure β-Lg aggregates, mainly through interaction of CNs with unfolded β-Lg and also by influencing the process of β-Lg unfolding. This was further confirmed by small angle X-ray scattering and isothermal titration calorimetry indicating that Ca2+ enhanced the interaction between β-Lg and CNs. Our experimental approach sheds light on molecular understanding of CN- β-Lg interactions and provides insight into how micro-structural assembly of milk proteins can be modulated to enable different functionalities in milk-based products.

KW - Aggregation propensity

KW - Caseins

KW - Chaperone

KW - Colloidal stability

KW - Milk

KW - β-lactoglobulin

U2 - 10.1016/j.foodhyd.2022.108373

DO - 10.1016/j.foodhyd.2022.108373

M3 - Journal article

AN - SCOPUS:85144077128

VL - 137

JO - Food Hydrocolloids

JF - Food Hydrocolloids

SN - 0268-005X

M1 - 108373

ER -