High-Fibre Banana Powder.

The researchers applied starch liquefaction to eliminate the high starch content present in the fruit and thereby produce a fibre-rich powder capable of being formulated in a variety of diverse functional foods.

Using commercial unripe (hard green) bananas, the liquefied slurry was then mixed with an alpha-amylase enzyme for three hours. After this time, the enzyme was inactivated, and the material centrifuged and dried to obtain the fibre-rich powder.

Compared to normal banana flour, the researchers report that the fibre-rich powder of banana flour contained 200 per cent more total dietary fibre, 32 per cent less starch, 88 per cent less resistant starch, and 32 per cent less available starch.

Moreover, the insoluble indigestible fraction was higher in the fibre-rich powder, compared to the plain banana flour (61 versus 44 grams, respectively).

The researchers also report that the powder contained high levels of extractable polyphenols that exhibited antioxidant activity similar to that of apple fibre

"A very fast reduction of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical was observed in the presence of fibre-rich powder (FRP), indicating that polyphenols in this preparation efficiently quench free radicals," they wrote.

"FRP might be a potential ingredient for development of products with high total dietary fibre and indigestible fraction contents, as well as important antioxidant capacity," they concluded.

Only recently, researchers from Nova Scotia Agricultural College in Canada reported that apple skin, an under-utilised food-processing by-product, could offer the food industry a novel and healthy-boosting source of fibre for bakery.

Incorporation of apple skin powder into muffins were found to be higher in fibre and have a higher antioxidant content than standard muffins, they reported in Food Chemistry.

Insoluble fibre contains cellulose, hemicellulose and lignin and cannot be dissolved in water, unlike soluble fibre. It is found in wheat or cereal bran and in most vegetables and fruits.

Consumption of insoluble fibre has previously been associated with a reduced risk of obesity and diabetes.

Product Description

Banana powder processing line, the craft procedure:

1. Raw material chosen
2. Color protection
3. Pulping
4. Homogenizer
5. Heating
6. Spray and drying
7. Packaging
8. Finished products