Ultrasound assisted extraction of pectin from banana peel waste as a potential source for pectin production

BACKGROUND: Large quantities of banana peels are discarded as waste or used as cattle feed or fertilisers. Moreover, the use of banana peel waste is considered to be a valuable polysaccharide like pectin that is valued by both pharmaceutical and food industries. It is well known that pectin is a high-value functional food ingredient widely used due to its special functional properties. METHODS: Pectin was extracted from banana peel waste using ultrasound assisted extraction (UAE) and the extraction was optimised by response surface methodology. The independent variables such as extraction temperature, sonication time and pH of a solution were used in the range of 35–45°C, 10–20 min, and 1–3, respectively. RESULTS: The overall optimal conditions of multiple responses were achieved at an extraction temperature of 33.12°C, sonication time of 17.12 min and pH of 3.68. Under these conditions, the predicted value of pectin yield, the degree of esterification and galacturonic acid content, were 2.62%, 88.26% and 87%, respectively. The experimental values were well correlated with the predicted values and revealed a satisfactory validation through real-time experiments, which was accomplished at optimised conditions. The physico-chemical properties of extracted pectin using optimal conditions were comparable to commercial pectin. CONCLUSIONS: The results obtained revealed that pectin was effectively extracted from the banana peel waste using UAE, which confirmed that it has potential as a source for the food, beverage and pharmaceutical industries. Further studies should be conducted to improve the quality of pectin and explore the bioactivity potential of pectin such as antimicrobial, prebiotic and antioxidant properties.