Performance of egg white and hydroxypropylmethylcellulose mixtures on gelation and foaming

The aims of this research were: i) to investigate phase separation behavior of egg white (EW) and hydroxypropylmethylcellulose (HPMC) mixtures at pH 7 (EW natural pH) or 3 (below EW proteins isoelectric point); ii) to study the impact of this segregation on gelation and foaming properties of the mix...

Descripción completa

Detalles Bibliográficos
Autores: Berg, Merel van den, Jara, Federico Luis, Pilosof, Ana Maria Renata
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/42725
Acceso en línea:http://hdl.handle.net/11336/42725
Access Level:acceso abierto
Palabra clave:Egg White
Hydroxypropylmethylcellulose
Phase Separation
Gelation Properties
Foaming Properties
Ph-Dependence
https://purl.org/becyt/ford/2.10
https://purl.org/becyt/ford/2
Descripción
Sumario:The aims of this research were: i) to investigate phase separation behavior of egg white (EW) and hydroxypropylmethylcellulose (HPMC) mixtures at pH 7 (EW natural pH) or 3 (below EW proteins isoelectric point); ii) to study the impact of this segregation on gelation and foaming properties of the mixed systems as compared to single EW. A sudden phase separation took place at pH 7, while at pH 3 occurred gradually and slowly. In confocal microscopy, fluorescence of EW and HPMC was found on the same locations, indicating complex formation. At pH 7 complexation was more pronounced and the complexes flocculated to form bigger particles bringing on the sudden macroscopic phase separation. At pH 3 the complexes were smaller and did not flocculate with time. The mixtures gelation temperature (Tgel) was similar to HPMC Tgel; however, the storage modulus (G′) initially similar to that of HPMC was then dominated by the protein. A synergism between EW and HPMC regarding G′ was found at both pHs, being this effect higher at pH 3. For textural properties, an improvement on hardness and springiness was found at pH 3. Regarding foaming properties, there was a synergistic effect on foam collapse at pH 3, while foam overrun slightly decreased and drainage did not show differences as compared to single EW. Thus, although depending on pH conditions, it is possible to improve gelation and foaming of EW by adding HPMC. Improvement was mostly found below the iso-electric point of EW.