Functional properties and in vitro starch digestibility of infrared‐treated (micronized) green banana flour

Abstract

BACKGROUND The consumption of green banana flour (GBF) products has been linked to reduced glycemic index (GI) and low risk of type 2 diabetes and obesity. The purpose of this study was to investigate the effect of micronization (high‐intensity infrared heating method) on the molecular, microstructure and in vitro starch digestibility of five GBF cultivars grown in South Africa. The GBF was micronized at three surface temperatures (90, 120 and 150 °C for 30 min) and the in vitro starch digestibility was determined with Megazyme kits. RESULTS Micronization at the highest temperature (150 °C) increased the swelling power by 6.00% in all five GBF cultivars when compared to control (unmicronized GBF). Micronization slightly reduced the resistant starch (RS) of the GBF cultivars by up to 8.63%. The FHIA‐01 cultivar showed the highest RS (86.50%), whereas Grande Naine – 150 °C cultivar had the lowest RS (76.00%). Both micronized and control GBF exhibited similar X‐ray diffraction patterns with all cultivars and at all micronization temperatures. Similarly, the functional properties of the GBF were not altered by micronization when observed with Fourier transform infrared spectroscopy. Scanning electron microscopy showed changes in the surface morphology of starch granules after micronization and these were dependent on temperature. CONCLUSION Overall, micronization at 120 °C showed the best improvement in functional properties of GBF and this makes it suitable for potential application for the manufacture of instant breakfast products, baked goods and pasta. In addition, the micronized GBF cultivars retained high RS, suggesting potential health benefits for people with diabetes and obesity. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Effect Evaluation of Banana on Improving Hyperglycemia and Hypertension in Diabetic Spontaneously Hypertensive Rats

“…Taken together, banana is a healthy fruit, and a beneficial resource of starch can be recommended to produce various staple foods, such as noodles, pasta, or bread, to prevent DM conveniently. [15][16][17][18][19][20] Whether banana still has similar effects after it is made into food remains to be studied. To analyze the bioactivities and applications of banana production will be the next challenge.…”

“…17 This highly prevalent fruit and related products, such as flour, are well worth studying in depth, particularly regarding its potential in preventing and treating T2DM and the associated disorders. 18,19 In this study, we used dried and milled unripe green banana (BN) as the protagonist to analyze its composition, efficacy, and pharmacological mechanism for anti-DM effects. We induced T2DM in spontaneously hypertensive rats (SHR) by injecting streptozocin (STZ) and nicotinamide (NA) and feeding them either a regular diet, a high-fat diet (HFD), or an HFD having carbohydrate content replaced with BN.…”

“…17 This highly prevalent fruit and related products, such as flour, are well worth studying in depth, particularly regarding its potential in preventing and treating T2DM and the associated disorders. 18,19…”