Green banana (Musa cavendishii) flour obtained in spouted bed – Effect of drying on physico-chemical, functional and morphological characteristics of the starch

This study aimed to characterize green banana flour obtained by drying in a spouted bed, and to evaluate the functional properties (viscosity, swelling power and solubility), as well as the physical, morphological and hygroscopic behaviour (sorption isotherm). The results show that the rheological behaviour of flour with peel showed the highest values of viscosities but both flour showed high tendency to retrogradation. The swelling power and solubility were also similar for all flour samples, with low solubility under cold and high solubility under hot conditions. The starch granules diameter ranged from 70 to 110 μm, with flattened and elongated morphology. The sorption isotherms were of type II (unpeeled banana flour) and III (peeled banana flour), and the BET model provided the best fit to the data, obtaining values for the monolayer adsorption of 5.78 and 4.34, respectively, and desorption of 4.85 and 4.14, respectively.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Spouted bed drying of green banana as a mild processing of banana flour. ► Green banana flour unpeeled as source of resistant starch. ► Green banana flour unpeeled as source of fibre and minerals.