Characterisation of the stability for suberin-in-water emulsions

Abstract

This thesis focuses on investigating the stability of suberin-in-water emulsions using commercial surfactants, i.e., Spans and Tweens, and hemicellulose derivatives as surfactants. Suberin, a natural biopolymer found in the cell walls of plants, has gained attention as a potential bio-friendly alternative in various applications. The objectives of this study were to determine the hydrophilic-lipophilic balance (HLB) of suberin, analyse the stability of the emulsions, and assess the suitability of hemicellulose-grafted-fatty acids (HC-FA) as surfactants for these emulsions. Experimental methods involved determining the HLB of suberin, formulating emulsions using hemicellulose derivatives as surfactants, and evaluating the stability of the emulsions. Emulsions stabilized with Spans and Tweens exhibited strong colloidal stability, while emulsions stabilized with galactoglucomannan-grafted-fatty acids (GGM-FA), a natural surfactant, displayed its potential by producing stable emulsions. The average zeta potential of around -25 mV also showed GGM-FAs potential for creating stable emulsions, despite microscopic observations confirming the presence of particle clusters. Overall, the findings contribute to understanding the stability of suberin emulsions and the potential application of hemicellulose derivatives as surfactants, providing valuable insights for the packaging and coating industries.