Banana peel flour shown to boost nutrition levels in baked goods

Banana peel or skin is making its way onto the plates of resourceful consumers, replacing pork in ‘pulled peel’ sandwiches and getting fried up into ‘bacon’.

It has now been revealed that incorporating banana peel flour into sugar cookie batter makes the treats more healthful. In taste tests, cookies enriched with some banana peel flour were more satisfying than those baked with wheat flour alone, claim researchers reporting in ACS Food Science & Technology.

Amid rising interest in plant-based diets and in ways of reducing food waste, food businesses and end consumers are seeking creative ways to use every part of their vegetables and fruits.

Chefs and home cooks are experimenting with banana peels, but these skins are extremely fibrous, making them unpleasant to eat raw.

Scientists recently found that they can grind the peels into a flour that’s rich in fibre, magnesium, potassium and antioxidant compounds. When small amounts of wheat flour in breads and cakes were replaced with the new flour, the baked goods were more nutritious and had acceptable flavours.

Researchers at Aligarh Muslim University in India decided to go further and conduct similar experiments with cookies, substituting some of the wheat flour in sugar cookies with banana peel flour, then assessing the cookies’ nutritional quality, shelf-stability and consumer acceptance.

To make banana peel flour, the researchers peeled ripe, undamaged bananas and then blanched, dried and ground the skins into a fine powder. They mixed together different amounts of the powder with butter, skimmed milk powder, powdered sugar, vegetable oil and wheat flour, creating five batches of sugar cookies, and baked them.

They discovered that increasing the amount of the banana peel flour from 0 to 15% in the batches produced browner and harder products, which could be a result of the increased fibre content from the peels. In addition, cookies with banana peel flour had less fat and protein, higher amounts of phenols and better antioxidant activities than the conventional ones. A trained panel determined that cookies with the smallest substitution of banana peel flour (7.5%) had the best texture and highest overall acceptability compared to the other batches.

“This batch also kept well for three months at room temperature — it tasted the same as the wheat-only versions after the lengthy storage period,” wrote lead author Faizan Ahmad. Because cookies can be enriched with some banana peel flour without impacting their consumer acceptance, the researchers say this addition could make these baked goods more nutritious.