Role of hydrocolloids in improving the physical and textural characteristics of fennel bread

Four different hydrocolloids, carageenan, carboxymethyl cellulose, guar gum and xanthan were administered at four different levels of substitution, 0.25, 0.5, 0.75 and 1.0% to 7.0% (w/w) fennel fortified bread to study the effects of hydrocolloids as texture improver. Physical properties like loaf weight were mostly unchanged while addition of hydrocolloid seems to have a positive effect on loaf volume. Crumb firming kinetics of the breads was investigated on storage using the Avrami model. Results seemed to suggest that application of hydrocolloids at lower levels slowed the firming kinetics. Crumb grain properties were studied using image analysis which suggested an increased number of cells and a lower average cell size for hydrocolloid substituted breads. Effect of hydrocolloids was further reasoned by an inverse relation between the specific volume and the average cell size of the bread samples. Rheological parameters such as G* was seen to increase on hydrocolloid addition suggesting increased rigidity in the samples.