FORTIFICATION OF OXIDESED STARCHES WITH Cu2+ IONS

The aim of the work was to establish the effect of the enrichment with copper ions on the gelatinisation parameters and water dynamics of pastes of commercial oxidised starches with different degree of substitution. Native potato starch was used as reference material. Test samples were analysed employing differential scanning calorimetry (DSC) as well as low field nuclear magnetic resonance (LF-NMR). It was stated that oxidized starches effectively adsorb microelements what makes them appropriate carrier for food fortification. Efficiency of adsorption increases with the increase in degree of substitution with carboxyl groups. This proves the ionic mechanism of this process. Slight degree of substitution with carboxyl groups resulted in minor changes in gelatinization parameters of starch both in plain and fortified starches. In spite that fortification with copper ions does not change the gelatinisation energy, it limits the molecular dynamics of water in pastes of enriched starches as compared to non-enriched ones. This is evidenced by the increase in correlation time tau(c) determined by the low-field NMR method.