Exploring the relationship between protein secondary structures, temperature-dependent viscosities, and technological treatments in egg yolk and LDL by FTIR and rheology.
Food Chem
; 173: 584-93, 2015 Apr 15.
Article
em En
| MEDLINE
| ID: mdl-25466063
ABSTRACT
Egg yolk and its main component, low-density lipoproteins (LDL), were consecutively pasteurised, optimally freeze-dried, and dispersed in various NaCl solutions (0-10%). Heat-induced changes in the protein secondary structures which accompanied viscosity-increasing aggregation processes were monitored using Fourier transform infrared spectroscopy (FTIR) to determine the intensities of intermolecular ß-sheets (1622 cm(-1)) and results were compared with the temperature-dependent viscosities. Considerable changes in secondary structures observed after reconstitution of freeze-dried LDL had no detectable effect on the characteristic heat-induced viscosity curves but suggest that LDL plays a particular role in the unwanted gel formation of egg yolk after conventional freezing. For all egg yolk samples and all NaCl-containing LDL samples, the sigmoidal changes in the absorbance units vs. temperature curves corresponded with the first increase in heat-induced viscosity. Both analytical methods showed that the presence of ionic strength caused a shift in curve progressions towards higher temperatures, indicating increased thermal stability.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Reologia
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Proteínas do Ovo
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Estrutura Secundária de Proteína
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Espectroscopia de Infravermelho com Transformada de Fourier
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Gema de Ovo
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Lipoproteínas LDL
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article