Ascorbic acid- and sodium ascorbate-loaded oxidized potato starch films: Comparative evaluation of physicochemical and antioxidant properties

The purpose of this study was to compare the effects of increasing concentrations of ascorbate ions (AIs, 0-100 mM) in the form of ascorbic acid (AA) and sodium ascorbate (SA) on the properties of edible oxidized potato starch films. The browning reactions were faster in the SA-added films than in those of AA-added. In, turn, AA recrystallized faster than its sodium salt. The highest concentration of SA increased the water vapor permeability of the films. The mechanical strength and stiffness of the films gradually decreased with the increase of AI content. Fourier-transform infrared spectroscopy spectra suggested that addition of SA provoked a more intensive structural changes in the films than AA. X-ray diffraction showed that 25 and 50 mM AI-added films exhibited higher crystanility than the control. The films with AA and SA did not differ in terms of dissolving behavior, ability to release AI, and consequently, antioxidant activity.