Lauric acid adsorbed cellulose nanocrystals retained the physical stability of oil-in-water Pickering emulsion during different dilutions, pH, and storage periods

Abstract Due to increased environmental and health concerns, there has been an increased demand for sustainable and natural emulsifiers/stabilizers to create a stable O/W emulsion. Due to their unique properties, cellulose nanocrystals (CNC) have been considerably investigated as a stabilizer for producing a stable emulsion. However, the utilization of CNC stabilized emulsion is only limited to viscous or semi-solid foods. Hence this study investigates the modification of CNC by adsorbing lauric acid and its suitability for producing a stable beta-carotene O/W Pickering emulsion for nutraceutical beverages and drinks. The efficacy of modified CNC on the physicochemical stability of the emulsion was monitored under different environmental conditions such as dilution factors of 1-10, pH of 1-11, and 30 days of storage period at room temperature. Results depicted that the modified CNC above 1.5% (w/v) significantly (p ≤ 0.05) retained the average droplet size, morphology, and creaming index at different dilutions. However, the droplet size increased by 150-300% for the emulsions stabilized with unmodified CNC with noticeable changes in creaming index and morphology of the droplets. Unexpectedly, higher thiobarbituric acid reactive substances (TBARS) concentrations were recorded for the emulsions stabilized by modified and unmodified CNC compared to the control emulsion, which contained gum arabic as a reference stabilizer. Transition metals in the CNC may have catalyzed lipid oxidation; however, their source and role in oxidation warrant further study.