We all know how important fibre is as a dietary ingredient Now, besides oat bran, dates, fenugreek, purslane and sweet potato greens are adding their names to the list of dietary fibre-providing edible items.
Several scientists and business leaders recently convened to discuss novel sources and functions of dietary fibre at the Institute of Food Technologists' Annual Meeting and Food Expo in New Orleans.
"These sources create great opportunities for the food industry," said Cal Kelly, president of Emerald Seed Products in Saskatchewan, Canada, where his company cultivates and processes legumes and fenugreeks for fibre.
"Consumers are aware that fibre is good for us and that we need to eat more of it," Kelly added.
Fibre helps to regulate appetite by creating a feeling of satiety. It enhances intestinal health and modulates blood sugar. In addition, fibre reduces low density lipoprotein and increases high-density lipoprotein (the good cholesterol). Fibre has roles in adding texture to food, providing low stabilization and replacing fats.
In the United Arab Emirates, where dates are a major component of individual diets, the fruit's fibre is having a favourable role in baked goods, so date cultivation is encouraged.
By reducing flour and replacing it with date fibre by 10 to 30 percent, breads, cookies and muffins have become as tasty as their flour counterparts but healthier.
However, with more date fibre, the volume of a loaf of bread shrunk too much, said Isameldin Hashim, Ph.D.
Purslane, a green familiar to Mediterranean diets but not to western ones, is high in dietary fibre, omega-3 fatty acids and phytochemicals. In terms of the amount of dietary fibre it contains, it exceeds other green vegetables like green lettuce and spinach, said Norma Dawkins, Ph.D., with Tuskegee University's food science department in Tuskegee, Ala.
Her research shows that sweet potato greens, part of the vine, match purslane's dietary fibre power and add Vitamin B and beta-carotene to the diet. Purslane and sweet potato grains also appear to have roles in reducing heart disease and cancer, but more studies are needed, Dawkins said.
Making false claims about sources of dietary fibre will turn off the consumer, said Sakharam Patil, PhD, president of a global business consulting firm.
He sees potential for more dietary fibre in fast food: "We don't chew that stuff. We just swallow it."
Ultimately, sophisticated tastes will rule what dietary fibre sources will be the most successful, Patil adds.
Kelly said: "Taste is the final arbiter of whether it will work in the marketplace."