Competitive displacement of sodium caseinate by low-molecular-weight emulsifiers and the effects on emulsion texture and rheology.

Autor: Munk MB; Palsgaard A/S, Palsgaardvej 10, DK-7130 Juelsminde, Denmark., Larsen FH, van den Berg FW, Knudsen JC, Andersen ML
Jazyk: angličtina
Zdroj: Langmuir : the ACS journal of surfaces and colloids [Langmuir] 2014 Jul 29; Vol. 30 (29), pp. 8687-96. Date of Electronic Publication: 2014 Jul 15.
DOI: 10.1021/la5011743
Abstrakt: Low-molecular-weight (LMW) emulsifiers are used to promote controlled destabilization in many dairy-type emulsions in order to obtain stable foams in whippable products. The relation between fat globule aggregation induced by three LMW emulsifiers, lactic acid ester of monoglyceride (LACTEM), saturated monoglyceride (GMS), and unsaturated monoglyceride (GMU) and their effect on interfacial protein displacement was investigated. It was found that protein displacement by LMW emulsifiers was not necessary for fat globule aggregation in emulsions, and conversely fat globule aggregation was not necessarily accompanied by protein displacement. The three LMW emulsifiers had very different effects on emulsions. LACTEM induced shear instability of emulsions, which was accompanied by protein displacement. High stability was characteristic for emulsions with GMS where protein was displaced from the interface. Emulsions containing GMU were semisolid, but only low concentrations of protein were detected in the separated serum phase. The effects of LACTEM, GMS, and GMU may be explained by three different mechanisms involving formation of interfacial α-gel, pickering stabilization and increased exposure of bound casein to the water phase. The latter may facilitate partial coalescence. Stabilizing hydrocolloids did not have any effect on the LMW emulsifiers' ability to induce protein displacement.
Databáze: MEDLINE