FOOD. Science. Technology. Quality

Food. SCIENCE. Technology. Quality

Food. Science. TECHNOLOGY. Quality

Food. Science. Technology. QUALITY




Functional properties of the modified starches fortified by copper ions


The objective of the paper was to estimate the usefulness of the most common, commercial starches modified as carriers of mineral components. Diverse food starches modified were investigated, differing in both the applied method of their modification and their substitution degree. The adsorption process of copper ions was carried out from the salt solution in the starch slurry below the pasting temperature. The following was determined: content of copper in starch samples investigated – using an AAS method; the course of the pasting process – using a Brabender method); changes in the colour – by measuring the colour using the systems of CIE, Yxy, and L*a*b*. The crystal structure was analyzed by an X-ray diffractometry method, and the mechanism of binding the CuII ions was determined using an EPR method. It was found that all the starches investigated effectively adsorbed copper ions, and could be applied as carriers of minerals in the food fortification processes, and, in addition, the hydrophilic or hydrophobic character of modifying groups impacted the adsorption process. The presence of polar carboxyl groups increased the effectiveness of adsorption whereas the presence of non-polar acetyl groups decreased its efficiency. The copper ions were evenly distributed within the whole sample and no residues of salt used in the adsorption were found. The presence of adsorbed copper ions did not impact the type of crystal structure of modified starches. When copper ions were used to fortify starches, the colour of the preparations obtained slightly changed, and their rheological properties were modified to a small extent. Minor changes in the usable properties permit to recommend all the preparations investigated as carriers of mineral components in foodstuffs.


starch: modified, oxidized, acetylated, crosslinked; copper, fortification