Sustainable Superheated Steam Drying of Unripe Banana (Musa acuminata cv. Hom Thong): Effects on Resistant Starch and Physicochemical–Functional Properties

Abstract

Utilizing unripe banana flour (UBF) has gained considerable interest recently due to its functional components, particularly its resistant starch (RS). This study explored the novel approach of superheated steam drying (SSD) to produce UBF. Banana slices with 1, 2, or 3 mm thicknesses were dried using SSD at 75, 85, 95, or 105°C. The resulting UBFs were analyzed for starch content and physicochemical‐functional properties and compared with conventional hot‐air drying (HAD) at 55 or 75°C. Replacing HAD with SSD saved 75% of the drying time and increased the whiteness index. SSD‐produced UBF had a high RS content, excellent resistance to enzyme digestion, and potential beneficial health effects. At the same time, scanning electron microscopy showed that the SSD‐ and HAD‐dried samples had similar morphological characteristics. The swelling power, water solubility index, and water holding capacity of the UBF increased rapidly above 70˚C. The peak viscosity, breakdown, and setback of SSD‐dried UBF were greater than those of HAD at the same temperature. Technological properties (high hydration value and peak viscosity) and reduced processing time make SSD‐dried UBF a potential natural thickening ingredient for the food industry.This article is protected by copyright. All rights reserved