Ultrasound-assisted extraction and spray-drying microencapsulation of Moringa oleifera leaf extract: effects of core–wall ratio and drying temperature on powder properties

Moringa oleifera leaves contain a high level of bioactive compounds that possess strong antioxidant potential. However, their incorporation into food systems is currently limited due to their poor dispersibility and instability. This study investigated the combined application of ultrasound-assisted extraction (UAE) and spray-drying microencapsulation to produce stable powdered extracts of Moringa Oleifera leaves. Methanolic extracts obtained through UAE were encapsulated using maltodextrin as a wall material at different core-to-wall ratios (0.1:10, 0.2:10, and 0.3:10, w/w) and inlet air temperatures (140, 150, and 160 °C). The resulting powder was assessed for particle distribution size, color characteristics, encapsulation efficiency, morphology, moisture content, density, hydration, and hygroscopicity properties. The encapsulation efficiency varied between 52.6% and 74.6%, but the high efficiencies were seen at lower core loading ratios. Scanning electron microscopy revealed spherical microcapsules with slightly wrinkled surfaces, peculiar to spray-dried powders. The moisture content ranged from 3.1 5.4% while water activity remained below 0.55, which indicates good storage stability. Interestingly, the powders showed a high water-solubility index (>90 %), which is attributed to the hydrophilic nature of maltodextrin. Conclusively, the findings indicate that the UAE with spray-drying microencapsulation is an excellent method of converting M. oleifera leaf extract into a stable, highly soluble powder, which is physically stable and suitable for functional food applications. The identified processing conditions provide a practical basis for the incorporation of M. oleifera bioactives into numerous functional food formulations.

Text 125481.pdf - Published Version Available under License Creative Commons Attribution. Download (545kB) Official URL or Download Paper: https://www.tjnpr.org/index.php/home/article/view/...

Actions (login required)

View Item