Microencapsulation of ultrasound-extracted betalains: Invitro anti-oxidant activity, thermal behavior & release profile

Abstract

This study explores the influence of Ultrasound-Assisted Extraction (UAE) on enhancing the extraction efficiency of total betalains (betacyanins and betaxanthins). Optimal ultrasound-assisted extraction parameters were determined as 20 min at 50 % amplitude through optimization experiment. The encapsulation process involved freeze-drying, using maltodextrin, xanthan gum, and their combination as wall materials.The resulting microcapsules were evaluated for encapsulation efficiency, total betalain content, and antioxidant activity. Microcapsules produced with a combination of wall materials, compared to individual wall materials, exhibited superior betalain stability, higher encapsulation efficiency (90.05 %), high betalain content (535.15 mg/100g), and high antioxidant activity (41.22 % DPPH inhibition and 84.13 % ABTS inhibition). The combination of wall materials resulted in enhanced stability and excellent physical properties, with high retention of bioactive compounds and antioxidants, offering promising applications in the food and nutraceutical industries.