Formulation of banana aroma impact ester in water-based microemulsion nano-delivery system for flavoring applications using sucrose laurate surfactant

Abstract

This investigation aims to formulate a dilutable water-based microemulsion nano-delivery system that can deliver flavor model ester to food or beverage without using organic solvents. Isoamyl acetate (IAA) was used as a simple model of hydrophobic flavoring ester that can impart banana aroma and flavor. Food-grade sucrose laurate was used as non-ionic surfactant at concentration of 5.0% (w/w). Different aqueous phases were used to formulate the microemulsions including pure water and aqueous solutions containing citric acid with sucrose, fructose and glucose, which are frequently used in food and beverage industries. The oil titration method was used to formulate the IAA-in- water microemulsions. Results indicated that sucrose laurate at 5.0% can form micelles having a particle size 1.3nm- 2.1nm depending on the sugar composition of the aqueous micellar solutions. Pure water micellar solution was able to solubilize the largest load of IAA (110μl/10g micellar solution ∼ 1.434 mmol/g surfactant) in the form of water continuous microemulsion. This value was declined to 80μl, 70μl and 60μl (∼1.044, 0.912 and 0.783 mmol/g surfactant) when the aqueous micellar solutions were composed of water/citric/sucrose, water/citric/fructose and water/citric/glucose, respectively. The particle size of all formulated microemulsions at the largest solubilized load of IAA ranged from 4.27nm to 6.24nm depending on the sugar composition of the aqueous phase. All formulations possessed a potent banana aroma and can be diluted with the corresponding aqueous phase up to 10- folds without losing their microstructure. The formulated microemulsions can be considered as basic nano-delivery models that can potentially be developed and rounded-up by addition of more aroma impact constituents to suite different applications in food and beverage flavoring industry.