Blend of renewable bio-based polymers for oil encapsulation: Control of the emulsion stability and scaffolds of the microcapsule by the gummy exudate of Prosopis nigra

Abstract

This work concern with the use of a novel mesquite gum as a biopolymer alternative in desert areas of northern Argentina. The species collected was taxonomically identified as Prosopis nigra based on morphological/histological characteristics. Its gummy exudate was partially purified (PN-biopolymer) showed antioxidant activity and good emulsifying properties. The emulsions at 10% PN-biopolymer showed EI24 values >0.50 even after a thermal shock with a relatively high oil volume fraction of 50%. pH-stability tests showed a correlation between fatty acid unsaturations and droplet size distribution. Then, the use of PN-biopolymer-alginate blend was evaluated for fish oil encapsulation. An external gelation process was optimized showed a significant dependence of the responses evaluated (EI24 and sphericity factor) towards the interaction between both polymers and the water/oil ratio. Thus, for a fixed oil/water ratio of 0.25, the appropriate amount of both polymers allowed to obtain an EI24 of 96.1% with sphericity factors of 0.971. The PN-biopolymer played a key role in the orderly alginate crosslinking by control emulsion stability. Based on this results, this biopolymer is a renewable, sustainable, and local resource for industrial applications.