Tecnologia de Alimentos
URI permanente desta comunidadehttps://locus.ufv.br/handle/123456789/11783
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Item Stability of casein micelles cross-linked with genipin: A physicochemical study as a function of pH(International Dairy Journal, 2017-05) Casanova, Federico; Silva, Naaman F. Nogueira; Gaucheron, Frédéric; Nogueira, Márcio H.; Teixeira, Alvaro V. N. C.; Perrone, Italo Tuler; Alves, Maura Pinhero; Fidelis, Priscila Cardoso; Carvalho, Antônio F. deChemical or enzymatic cross-linking of casein micelles (CMs) increases their stability against dissociating agents. In this paper, a comparative study of stability between native CMs and CMs cross-linked with genipin (CMs-GP) as a function of pH is described. Stability to temperature and ethanol were investigated in the pH range 2.0e7.0. The size and the charge ( z -potential) of the particles were determined by dynamic light scattering. Native CMs precipitated below pH 5.5; CMs-GP precipitated from pH 3.5 to 4.5, whereas no precipitation was observed at pH 2.0e3.0 or pH 4.5e7.0. The isoelectric point of CMs-GP was determined to be pH 3.7. Highest stability against heat and ethanol was observed for CMs-GP at pH 2, where visible coagulation was determined only after 800 s at 140 C or 87.5% (v/v) of ethanol. These results confirmed the hypothesis that cross-linking by GP increased the stability of CMs.