INVESTIGADORES
BIERBRAUER Karina Lilian
artículos
Título:
Effect of ethylcellulose on the structure and stability of non-aqueous oil based
Autor/es:
MARCELO R. CEBALLOS; VALENTINA BRAILOVSKY; KARINA L. BIERBRAUER; SILVIA L. CUFFINI; DANTE M. BELTRAMO; ISMAEL D. BIANCO
Revista:
FOOD RESEARCH INTERNATIONAL
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2014 vol. 62 p. 416 - 423
ISSN:
0963-9969
Resumen:
The hydrophobic polymer ethylcellulose (EC) has been used to structure
vegetable oils and as stabilizer of oil/water (o/w) emulsions, among other non
food uses. In this work we show that EC dissolved in medium chain triglycerides
(MCT) or soybean oil (SO) is able to stabilize non-aqueous emulsions of
propylene glycol (PG) as a dispersed phase. Cream-like emulsions can be
obtained at both low and high homogenization speeds which show a very good
stability for at least one month without the requirement of co-surfactants. PG-inoil
emulsions at concentrations of EC below 5 % (w/w) display pseudoplastic
behavior and greater viscosity than the respective solutions of the polymer in
MCT or SO. However, at concentrations of EC above 5 % (w/w) firm gels are
formed in MCT or SO and after the addition of PG, the emulsions formed have
lower viscosity than the original solutions of the polymer in MCT or SO. Such
effects were independent of the mean molecular weight (MMW) of the EC at
high shear stress and inversely proportional at low shear stress. These results
indicate that the stabilizing effect of EC in PG-in-oil emulsions might not be
caused mainly by an increase in viscosity of the continuous phase. Comparing
all the results obtained, we can infer that EC, despite being insoluble in PG, is
promoting interactions which are responsible for the observed effects.
These PG-in-oil emulsions have interesting structural and flow properties which
make them attractive to be used in food formulations, either as emulsions
themselves or as potential vehicles for active ingredients.