Mango peel, usually discarded during mango processing, was used as a rich source of dietary fibre and formulated into soft dough biscuits that passed a consumer acceptance test, according to the findings in the Journal of Cereal Science .
The research, by scientists at India's Central Food Technological Research Institute, adds to earlier reports of the potential of mango to increase dietary fibre.
Interest in dietary fibre has been increasing with scientific studies linking increased intake to reduced risks of cancers such as colorectal, and cardiovascular disease.
As such, there is a trend to find new sources of dietary fibre as functional ingredients.
Despite the mounting evidence for the benefits of dietary fibre, a survey by Columbia University showed the average intake in the US was about 12.5 grams a day, well short of the 32 grams of fibre per day recommended by the US National Fiber Council.
"It may be concluded from the present study that mango peel powder (MPP) could be incorporated up to a 10 per cent level in the formulation of biscuits without affecting their overall quality," wrote the researchers, led by Ummiti Prasada Rao.
"Thus, mango peel, a by-product from the mango processing industry, could be utilised for the preparation of biscuits and other food products with improved functional and nutraceutical properties."
This is not the first time that researchers have looked at the potential of mango to boost the dietary fibre content of food.
Previously, researchers from Venezuela and Ecuador extracted dietary fibre from unripe mangoes and formulated them into cookies and bread, with good results reported in the journal LWT - Food Science and Technology (doi: 10.1016/j.lwt.2006.02.028).
The new research used a powder prepared from mango peel and found to contain 51.2 per cent total dietary fibre, 96 mg gallic acid equivalent per gram of polyphenols, and 3092 micrograms per gram of carotenoids.
The powder was then incorporated it into biscuits at differing concentrations, including 0, 2.5, 5, 7.5, 10, 15, and 20 per cent.
The highest level of MPP addition boosted fibre, polyphenol, and carotenoid content of the soft dough biscuits from 6.5 to 20.7 per cent, from 0.54 to 4.50 mg/g, from 17 to 247 micrograms/g, respectively.
However, this level adversely affected the sensory qualities of the biscuits, said the researchers.
"At 20 per cent level the biscuits had a slight bitter taste which may be due to high polyphenol content," they stated.
"Considering the colour, appearance, texture and flavuor attributes, it could be inferred that 10 per cent level of incorporation of MPP was optimum.
Therefore, biscuits of acceptable overall quality can be prepared using 10 per cent MPP formulations."
According to the FAO, global production of mango was almost 25m metric tonnes in 2000, increasing to just under 28m metric tonnes last year.
Almost 99.5 per cent of production is from developing countries.
Source: Journal of Cereal Science Published online ahead of print 22 November 2007, doi:
10.1016/j.jcs.2007.10.001 "Improvement of dietary fiber content and antioxidant properties in soft dough biscuits with the incorporation of mango peel powder" Authors: C.M. Ajila, K. Leelavathi and U.J.S. Prasada Rao