According to findings published in LWT - Food Science and Technology, researchers from the National Technical University of Athens found that adding three grams of maize fibre per 100 grams of dough produced the “highest score for overall acceptability”.
The study taps into the growing trend for enhanced gluten-free foods, a rapidly growing market. According to a recent report from Packaged Facts, the gluten-free market has grown at an average annual rate of 28 per cent since 2004, when it was valued at $580m, to reach $1.56bn last year. Packaged Facts estimates that sales will be worth $2.6bn by 2012.
“These studies have shown the potential of developing fibre-rich gluten-free breads in order to increase acceptability and dietary fibre intake,” wrote the authors.
The researchers decided to look into fibre-enrichment of gluten-free products since many people with coeliac disease may be at risk of low fibre intakes due to their dietary pattern.
Coeliac disease, a condition characterized by an intolerance to gluten in wheat, is reported to affect up to 1 per cent of children and 1.2 per cent of adults, according to a study in the BMJ’s Gut journal.
Fibre intake has been shown to benefit gastrointestinal health, glucose handling, heart health, cancer risk and satiety, but these benefits are dependent on the types of fibre present in foods.
Fibre formulations
The Athens-based researchers enriched gluten-free baked products based on corn starch (Roquette), rice flour (Mediterranean Farm SA) and hydroxypropyl methyl cellulose (HPMC, Dow Wolff Cellulosics) with dietary fibre with different cereal fibres, including maize and oat. Fibres were added at levels ranging from 3 to 9 grams per 100 g.
Both maize and oat fibres were found to improve the bread’s nutritional and sensory properties. The highest fibre content breads were rated lower on an acceptance scale than the breads with the lower doses (3 and 6 grams). The optimal results were observed for three grams of maize fibre.
“Addition of dietary fibre from maize and oat in gluten-free formulations gave breads with significantly higher loaf volume and crumb softness compared to the control non-fibre gluten-free bread,” wrote the researchers.
“These breads provide the consumer with higher amounts of total dietary fibre and had also an appealing dark crust and a uniform and finely grained crumb texture.”
Fibre definitions
The WHO/FAO definition of fibre, established in December 2007 (European Journal of Clinical Nutrition – Nishida et al 2007) describes fibre as intrinsic plant cell wall polysaccharides.
It says the term should be “reserved for cell wall polysaccharides of vegetables, fruit and wholegrains, the health benefits of which have been clearly established, rather than synthetic, isolated or purified oligosaccharides with diverse, and in some cases unique, physiological effects.”
Source: LWT - Food Science and Technology Published online ahead of print, doi: 10.1016/j.lwt.2009.03.010"Effect of dietary fibre enrichment on selected properties of gluten-free bread" Authors: D. Sabanis, D. Lebesi, C. Tzia