High acyl gellan as an emulsion stabilizer

Author(s)

Pires Vilela, Joice Aline ^[1] ; da Cunha, Rosiane Lopes ^[1]

Affiliation

^[1] Univ Estadual Campinas, Sch Food Engn, Dept Food Engn, BR-13083862 Campinas, SP - Brazil

• Document type: Journal article
• Source: Carbohydrate Polymers; v. 139, p. 115-124, MAR 30 2016.
• Web of Science Citations: 6

Abstract

High acyl gellan (0.01-0.2% w/w) was used as stabilizer in oil in water emulsions containing 30% (w/w) of sunflower oil and prepared under different process conditions. Stable emulsions to phase separation could be obtained using high acyl gellan (HA) content above 0.05% (w/w), while low acyl gellan (LA) prepared at the same conditions could not stabilize emulsions. Emulsions properties depended on the process used to mix the oil and gellan dispersion since high pressure homogenization favored stabilization while very high energy density applied by ultrasound led to systems destabilization. Emulsions prepared using high pressure homogenization showed zeta potential values ranging from -50 up to -59 mV, suggesting that electrostatic repulsion could be contributing to the systems stability. Rheological properties of continuous phase were also responsible for emulsions stabilization, since HA gellan dispersions showed high viscosity and gel-like behavior. The high viscosity of the continuous phase could be associated to the presence of high acyl gellan microgels/aggregates. Disentanglement of these aggregates performed by ultrasound strongly decreased the viscosity and consequently affected the emulsions behavior, reducing the stability to phase separation. (C) 2015 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 12/11794-5 - Study and preparation of polysaccharide nanoparticles to stabilize Pickering emulsions
• Grantee: Joice Aline Pires Vilela
• Support Opportunities: Scholarships in Brazil - Doctorate