The effect of commercial modified celluloses: microcrystalline cellulose, carboxymethyl cellulose, and hydroxypropylmethyl cellulose on bread quality attributes and their potential protective effect with respect to bread staling were analyzed. Two levels of gums were assayed (0.5 and 1.5 g/100 g flour).
The best performance was obtained with carboxymethyl cellulose and hydroxypropylmethyl cellulose F 4 M at both levels; these gums led to higher specific volumes and a better crumb texture as measured by texture profile analysis. In general, crumbs were softer, more cohesive, and resilient and exhibited lower chewiness values. Other gums like microcrystalline cellulose and hydroxypropylmethyl cellulose F50 did not improve bread quality on the same extent. Mechanical spectra obtained by dynamic mechanical analysis assays indicated a marked change in molecular mobility when carboxymethyl cellulose was present. Bread staling was evaluated by texture profile analysis, moisture loss, and calorimetric assays.
Gums did not avoid retrogradation and even exhibited an accelerating effect, probably due to changes in water retention and migration during storage. However, in most cases, final crumb hardness in samples with hydrocolloids was lower than that in the control sample.