Comparative study on chemical and emulsion properties of 'Saba' banana [Musa acuminata x balbisiana (BBB group) 'Saba'] peel pectin from different extraction methods

Abstract

This study was conducted to investigate the chemical characteristics and emulsion properties of pectin from 'Saba' banana peel extracted using three different methods, namely, acid extraction using citric acid, enzymatic extraction using cellulase, and microwave-assisted extraction. Per cent yield, moisture and ash contents, equivalent weights, methyl and anhydrouronic acid contents, and the degree of esterifications were determined for each pectin extracted using the three different methods. Characterization of the extracted pectin revealed that all 'Saba' peel pectins (SBPs) had a high degree of esterification. Furthermore, acid-extracted pectin (AP) had the highest yield of 20.02% and had the highest purity, as indicated by the lowest ash content and equivalent weight (784.57), and highest anhydrouronic acid content (50.85%) compared to enzymatic (EP) and microwave-assisted extraction (MP). Scanning Electron Microscopy revealed smoother images of AP, which indicated that AP was more degraded compared to milder extraction methods, such as microwave-assisted extraction which yielded the least degraded pectin. Furthermore, emulsion formation and stability using SBPs were determined by measuring cream fraction. Results showed that all SBPs had cream fractions comparable to the control, and there was no difference among extraction methods. Microscopic observations (10×) showed that oil droplet size decreases with increasing concentration. Further, AP had smaller droplets, indicating that AP is capable of forming more stable emulsions compared to EP and MP. Results of this investigation revealed that, although all SBPs were highly esterified, the three extraction methods yielded pectins with different characteristics and purity.