Premium
Heat‐induced denaturation and aggregation of β‐Lactoglobulin: kinetics of formation of hydrophobic and disulphide‐linked aggregates
Author(s) -
Galani Despina,
Apenten* Richard K.
Publication year - 1999
Publication title -
international journal of food science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.831
H-Index - 96
eISSN - 1365-2621
pISSN - 0950-5423
DOI - 10.1046/j.1365-2621.1999.00314.x
Subject(s) - chemistry , denaturation (fissile materials) , protein aggregation , arrhenius plot , fast protein liquid chromatography , kinetics , whey protein , covalent bond , chromatography , arrhenius equation , gel permeation chromatography , activation energy , organic chemistry , high performance liquid chromatography , nuclear chemistry , polymer , biochemistry , physics , quantum mechanics
Summary Solutions of a whey protein mixture were subjected to various time/temperature treatments, at pH 6.7. Kinetic and thermodynamic activation parameters for the rates of irreversible denaturation/aggregation of the principal whey protein component—β‐lactoglobulin (β‐lg) were followed by gel permeation. Fast Protein Liquid Chromatography (non‐dissociating, non‐reducing conditions) and by SDS‐PAGE (dissociating, non‐reducing conditions). The rate of loss of native β‐lg owing to the formation of disulphide linked protein aggregates (k sds‐page ) and the rate of formation of aggregates via both covalent and non‐covalent bonds (k gp‐fplc ) showed similar biphasic Arrhenius plots. However, the break of the plot occurred at different points. The k gp‐fplc values were higher than values of k sds‐page for all the temperatures examined. There was a similar trend for the thermodynamic activation parameters implying that not all of the β‐lg aggregates through thiol–disulphide interactions. Hydrophobically driven associations occur within the aggregates.