Casein glycomacropeptide pH-driven self-assembly and gelation upon heating

Casein glycomacropeptide (CMP) found in cheese whey is a C-terminal hydrophilic glycopeptide released from κ-casein by the action of chymosin during cheese making. In a previous work a self-assembly model for CMP at room temperature was proposed, involving a first step of hydrophobic assembly follow...

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Detalles Bibliográficos
Autores principales: Martínez, María Julia, Farías, María Edith, Pilosof, Ana María Renata
Publicado: 2011
Materias:
Casein glycomacropeptide
Heat gelation
Heat-induced self-assembly
PH
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0268005X_v25_n5_p860_Martinez
http://hdl.handle.net/20.500.12110/paper_0268005X_v25_n5_p860_Martinez
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id paper:paper_0268005X_v25_n5_p860_Martinez
record_format dspace
spelling paper:paper_0268005X_v25_n5_p860_Martinez2023-06-08T15:23:49Z Casein glycomacropeptide pH-driven self-assembly and gelation upon heating Martínez, María Julia Farías, María Edith Pilosof, Ana María Renata Casein glycomacropeptide Heat gelation Heat-induced self-assembly PH Casein glycomacropeptide (CMP) found in cheese whey is a C-terminal hydrophilic glycopeptide released from κ-casein by the action of chymosin during cheese making. In a previous work a self-assembly model for CMP at room temperature was proposed, involving a first step of hydrophobic assembly followed by a second step of electrostatic interactions which occurs below pH 4.5. The objective of the present work was to study, by dynamic light scattering (DLS), the effect of heating (35-85 °C) on the pH-driven CMP self-assembly and its impact on the dynamics of CMP gelation. The concentration of CMP was 3%. w/w for DLS and 12%. w/w for rheological measurements. The solutions at pH 4.5 and 6.5 did not show any change in the particle size distributions upon heating. In contrast the solutions at pH lower than 4.5 that showed electrostatic self-assembly at room temperature were affected by heating. The mean diameter of assembled CMP increased by decreasing pH. For all solutions with pH lower than 4.5, the particle size did not change on cooling, suggesting that the assembled CMP forms formed during heating were stable. The gel point determined as G'-G″ crossover, occurred in all systems at 70 °C, but at different times. The rate of self-assembly determined by DLS as well as the rate of gelation increased with increasing temperature and decreasing pH from 4 to 2. Increasing temperature and decreasing pH, the first step of CMP self-assembly by hydrophobic interactions is speed out. All the self-assembled structures and the gels formed at different temperatures were pH-reversible but did not revert to the initial size (monomer) but to associated forms that correspond mainly to CMP dimers. © 2010 Elsevier Ltd. Fil:Martinez, M.J. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Farías, M.E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Pilosof, A.M.R. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2011 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0268005X_v25_n5_p860_Martinez http://hdl.handle.net/20.500.12110/paper_0268005X_v25_n5_p860_Martinez
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Casein glycomacropeptide
Heat gelation
Heat-induced self-assembly
PH
spellingShingle Casein glycomacropeptide
Heat gelation
Heat-induced self-assembly
PH
Martínez, María Julia
Farías, María Edith
Pilosof, Ana María Renata
Casein glycomacropeptide pH-driven self-assembly and gelation upon heating
topic_facet Casein glycomacropeptide
Heat gelation
Heat-induced self-assembly
PH
description Casein glycomacropeptide (CMP) found in cheese whey is a C-terminal hydrophilic glycopeptide released from κ-casein by the action of chymosin during cheese making. In a previous work a self-assembly model for CMP at room temperature was proposed, involving a first step of hydrophobic assembly followed by a second step of electrostatic interactions which occurs below pH 4.5. The objective of the present work was to study, by dynamic light scattering (DLS), the effect of heating (35-85 °C) on the pH-driven CMP self-assembly and its impact on the dynamics of CMP gelation. The concentration of CMP was 3%. w/w for DLS and 12%. w/w for rheological measurements. The solutions at pH 4.5 and 6.5 did not show any change in the particle size distributions upon heating. In contrast the solutions at pH lower than 4.5 that showed electrostatic self-assembly at room temperature were affected by heating. The mean diameter of assembled CMP increased by decreasing pH. For all solutions with pH lower than 4.5, the particle size did not change on cooling, suggesting that the assembled CMP forms formed during heating were stable. The gel point determined as G'-G″ crossover, occurred in all systems at 70 °C, but at different times. The rate of self-assembly determined by DLS as well as the rate of gelation increased with increasing temperature and decreasing pH from 4 to 2. Increasing temperature and decreasing pH, the first step of CMP self-assembly by hydrophobic interactions is speed out. All the self-assembled structures and the gels formed at different temperatures were pH-reversible but did not revert to the initial size (monomer) but to associated forms that correspond mainly to CMP dimers. © 2010 Elsevier Ltd.
author Martínez, María Julia
Farías, María Edith
Pilosof, Ana María Renata
author_facet Martínez, María Julia
Farías, María Edith
Pilosof, Ana María Renata
author_sort Martínez, María Julia
title Casein glycomacropeptide pH-driven self-assembly and gelation upon heating
title_short Casein glycomacropeptide pH-driven self-assembly and gelation upon heating
title_full Casein glycomacropeptide pH-driven self-assembly and gelation upon heating
title_fullStr Casein glycomacropeptide pH-driven self-assembly and gelation upon heating
title_full_unstemmed Casein glycomacropeptide pH-driven self-assembly and gelation upon heating
title_sort casein glycomacropeptide ph-driven self-assembly and gelation upon heating
publishDate 2011
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0268005X_v25_n5_p860_Martinez
http://hdl.handle.net/20.500.12110/paper_0268005X_v25_n5_p860_Martinez
work_keys_str_mv AT martinezmariajulia caseinglycomacropeptidephdrivenselfassemblyandgelationuponheating
AT fariasmariaedith caseinglycomacropeptidephdrivenselfassemblyandgelationuponheating
AT pilosofanamariarenata caseinglycomacropeptidephdrivenselfassemblyandgelationuponheating
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