Production of unripe banana flour (Musa spp) for application in whole wheat bread

Abstract Unripe banana flour (UBF) is a viable alternative for using the fruit, since it has a high resistant starch (RS) content which presents a physiological role similar to that of dietary fibre. The objective of this study was to produce UBF from two banana genotypes (Lady Finger and Cavendish), and select the one with the highest level of RS for subsequent replacement of part of the whole wheat flour by UBF in a formulation for whole wheat loaves. For the production of UBF, the fruits were peeled, cut into slices, submerged in a solution of ascorbic acid and citric acid, spread on trays, dried at 50 °C for 7 hours and then ground. The flours were submitted to proximate composition and RS content analyses. Whole wheat loaves were then processed, replacing 10%, 15% and 20% of the whole wheat flour by the UBF containing the highest resistant starch content. The control loaves and the one with the highest RS content and good technological characteristics, such as specific volume, hardness and colour, were submitted to a sensory test for acceptance and purchase intent. The resistant starch contents found in the Finger and Cavendish UBF samples were 24.1% and 13.7% respectively. Loaves with 15% substitution of the whole wheat flour by UBF were chosen for the sensory analysis. The Control loaf formulation and that with 15% UBF reached acceptance levels of 88.7% and 82.1%, respectively. The attitude of the judges was positive since 56% of them answered they would buy the bread with 15% UBF frequently or always, and none of the formulations were rejected.