Effect of chemical acidification on gluten free bread characteristics

To reduce bread waste it is necessary to delay staling, that mainly involves starch reorganization and water loss. Sourdough acidification increases products shelf-life by maintaining bread softness and by protecting them from mould and bacterial spoilage. However, the sourdough process is a time consuming technology, difficult to manage. The aim of this study was to evaluate if dough acidification with lactic acid combined with a straight dough process could increase the shelf-life of gluten free (GF) bread. A traditional dough (T) and an acidified dough (A), both at 230 and 180 Brabender Unit (BU) consistency, were leavened by using compressed yeast. The resulting four doughs were characterized in terms of dough consistency, pH, dough development, and capability to produce and retain CO2. Both fresh and stored (up to 69h, at 25°C and 60%RH) breads were characterized for weight, height, specific volume, crust and crumb color, moisture, aw, and crumb hardness. The chemical acidification seemed to improve the GF dough leavening properties, as CO2 production and retention increased, resulting in a more developed dough. Significant (P<0.05) differences were also evidenced among the different GF breads. In general, well-developed breads were obtained, and both 180A and 230A samples showed higher specific volumes in comparison with T-breads, suggesting that the chemical acidification improved the doughs baking aptitude. As regards bread crumb softness, the higher amount of water added to the dough, rather than lactic acid addition, played a central role: the samples having a 180BU consistency, in fact, showed lower Young’s modulus during the entire storage period. Further studies are in progress to highlight the potential effect of chemical acidification during longer storage in a flexible packaging.