INFLUENCE OF STARCH-LIPID COMPLEXATION ON THE AGING BEHAVIOR OF HIGH-CONCENTRATION STARCH GELS

Rheological changes of high concentration starch gels, which served as bread models, were followed up during ageing. Potato, wheat and maize starch gels with and without emulsifier were prepared by heating nati ve starch suspensions (40g/100g) in closed moulds. The complexing glyc erolmonostearate and calciumstrearoyl-lactyl-2-lactylate and the non-c omplexing lecithin were used as emulsifiers. The complexing ability of emulsifiers and the amylopectin retrogradation were measured with dif ferential scanning calorimetry (DSC). The rheological changes of the s tarch gels during ageing were followed by uniaxial compressional tests . Starch complexation with complex forming emulsifiers accelerated the gelation of starch slightly, increasing the modulus of elasticity of freshly prepared gels. During ageing, the firmness increase of starch gels with complexes was slower than that of the lipid free control. Fu rthermore, the breaking stress of complexed starch gels was reduced af ter ageing. The antifirming effect of emulsifiers is mainly caused by amylose complexation, which in turn weakens the cohesion between the a mylopectin-rich starch granules.