The effect of hydrocolloids and surfactants on the physical properties of gluten free bread

Gluten is a fundamental component for the overall quality and structure of breads. The replacement of the gluten network in the development of gluten-free cereal products for people with celiac disease is a challenging task for the cereal technologist. The aim of this work was to evaluate the effect of hydrocolloids (Psyllium flour, hydroxypropylmethylcellulose (HPMC)) and surfactants (diacetyltartaric acid esters of monoglycerides - DATEM, and DIMODAN®) on the physical properties (height, weight, specific volume, color, crumb hardness) of gluten free (GF) bread during 4 days of storage. The formulation of GF bread was 75% flour mixture, 6% pea isolate, 3% hydrocolloid, 0.5% emulsifier, 6% olive oil, 4% sugar, 3.5% fresh yeast and 2% salt. The amount of water required to yield a dough consistency of 200 BU (Brabender units) was measured by farinograph and the dough development during leavening and the gas volume from the yeast activity were measured with the rheofermentometer. After this test, the formulations were chosen base on the values of gas retention coefficient (RC %= CO2 RET/ CO2 TOT) higher than 96%. The selected GF bread samples contained HPMC and HPMC/Psyllium flour at a ratio of 1:1 as hydrocolloids, and DATEM and DIMODAN® as surfactants. The water absorption and RC of these samples were in the range of 71.8-79.4% and 96.1-97.8%, respectively. During storage, the formulation with HPMC/Psyllium flour (1:1 w/w) and DATEM showed an anti-staling effect, retarding the crumb hardening. This GF bread sample had the lowest crumb hardness (20.9±1.1 N.