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Improvement of emulsifying properties of milk proteins with κ or λ carrageenan: effect of pH and ionic strength

Mena-Casanova, Edith, Totosaus, Alfonso
International journal of food science & technology 2011 v.46 no.3 pp. 535-541
carrageenan, caseinates, emulsifying properties, emulsions, ionic strength, isoelectric point, milk proteins, pH, sodium chloride
The objective of this work was to determine the effect of λ-carrageenan or κ-carrageenan on the emulsion capacity, emulsion work and emulsion stability of milk proteins concentrate (MP) or sodium caseinate (SC) emulsions at different levels of pH and ionic strength. Incorporation of carrageenans to proteins emulsions resulted in an improvement of emulsifying properties at pH 6.0 and low ionic strength (0.2 m NaCl). Although emulsion capacity was high in MP than for SC, irrespectively of carrageenan employed, addition of λ-carrageenan increased twofold emulsion work values (15 327 Ω s⁻¹ for MP and 11 455 Ω s⁻¹ for SC; around 6000 Ω s⁻¹ in the other treatments). Emulsion stability was high with λ-carrageenan (9.8 s) than MP-κ-carrageenan or MP (7.45 and 7.40 s, respectively). Carrageenan improving of emulsion properties was because of the complex formation with MP, characteristic of this type of food system when pH was above of isoelectric point.