The bean starch also reduced the crumb hardness of the test bread, and boosted its elasticity, potentially offering a better texture in the final loaf, according to findings published in the Journal of Food Processing and Preservation.
“To gain approval, gluten-free breads need to resemble wheat-flour bread,” explained scientists from the Polish Academy of Sciences and the Spanish Council for Scientific Research (CSIC). “This research provided the preliminary guidance to apply bean starch as the ingredient of gluten-free bread and determine its influence on the structure and texture behaviour of crumbs during storage.”
The findings could lead to enhanced products for the blossoming gluten-free food market, worth almost $1.6bn last year, according to Packaged Facts, and experiencing a compound annual growth rate of 28 per cent over four years.
Sufferers of coeliac disease have to avoid all gluten in their diet, but diagnosis is not the only factor. Other sectors of the population, such as those who have self-diagnosed wheat or gluten intolerance or who believe gluten-free to be a healthier way of eating, are also strong drivers.
Removing gluten poses technological challenges because the protein possesses unique properties which are vital for both the retention of gas during fermentation, and the preservation of moisture levels in the dough.
May current commercially available gluten-free breads are based mainly on starch, and are “characterised by low quality, exhibiting poor crumb and crust characteristics as well as poor mouth feel and flavour”, according to gluten-free researchers from the University of Cork (Food Microbiology, Vol. 26, pp. 676-684).
Potential of beans
The Polish and Spanish researchers evaluated the potential of a modified bean starch prepared in their laboratory. Breads were formulated with potato starch, cornstarch, and bean starch. Control bread was formulated by substituting the bean starch by additional cornstarch.
Results showed that the bean starch bread was softer with improved chemical composition and quality, said the researchers.
However, they do note that the freshness of the gluten-free bread was not extended during storage.
Additional research may improve the overall quality and acceptance of the resulting gluten-free bread.
Progress is being made in gluten-free formulations. Indeed, a brand called Genius was recently launched in the UK to much acclaim. Exclusive to retailer Tesco, the bread is formulated with water, potato starch, cornflour, vegetable oil, tapioca starch, egg white, rice bran, cellulose, xanthan gum as a stabiliser, sugar, yeast, rice flour, salt.
Source: Journal of Food Processing and Preservation
Volume 34, Pages: 501-518
“Bean starch as ingredient for gluten-free bread”
Authors: U. Krupa, C.M. Rosell, J. Sadowska, M. Sorel- Smietana