info:eu-repo/semantics/article
Effects of heat-treated β-lactoglobulin and its aggregates on foaming properties
Fecha
2011-07Registro en:
Moro, Andrea; Báez, Germán David; Busti, Pablo Andres; Ballerini, Griselda A.; Delorenzi, Nestor Jorge; Effects of heat-treated β-lactoglobulin and its aggregates on foaming properties; Elsevier; Food Hydrocolloids; 25; 5; 7-2011; 1009-1015
0268-005X
CONICET Digital
CONICET
Autor
Moro, Andrea
Báez, Germán David
Busti, Pablo Andres
Ballerini, Griselda A.
Delorenzi, Nestor Jorge
Resumen
The effects on foaming properties of the aggregates formed by heating concentrate beta-lactoglobulin solutions (55 mg mL-1, pH 6.8) at 85 °C from 1 to 15 min were investigated. Structural characteristics (size and molecular conformation), hydrophobicity and protein aggregates proportion were also studied. All tested methods pointed at 3 min of heating as a critical time, in terms of conformational changes and aggregation processes. At this time, the most significant conformational changes took place: non-native monomers were present and the greatest amount of dimers and trimers was produced, which was proved with the results of gel densitometry of SDS-PAGE, fluorescence quenching and circular dichroism tests. Foamability and foam stability were both improved by pre-heating the protein. A constant proportion among beta-lactoglobulin species (monomer 51%, dimer 33% and trimer 16%), regardless the protein concentration, led to the same results on foaming properties, confirming the link with structural changes. Aggregates formed by heating beta-lactoglobulin up to 10 min produced more stabilized foams, slowing down disproportionation, because of the formation of stiffer films. The increase in surface hydrophobicity was considered a decisive factor in the improved foamability and hydrophobic interactions improved the foam stability trough the rapid formation of a viscoelastic film. © 2010 Elsevier Ltd.