Influence of calcium fortification on the stability of anthocyanins in strawberry puree.

Anthocyanins have received an increased attention not only because of its antioxidant activity; but because fortification of food products by minerals is important due to the lack of some minerals in population. The addition of these minerals can affect the sensorial and nutritional composition of food. The influence of calcium fortification on anthocyanins and colour changes in strawberry puree were assessed by accelerated storage test. The quantification of anthocyanins was performed by high-performance liquid chromatography with diode-array detection (HPLC-DAD) and colour changes were measured spectrophotometrically (CIE L* – lightness, a* – redness, b* – yellowness). The kinetical parameters (velocity constants and activation energies) were calculated. The activation energies of degradation of anthocyanins were calculated as pelargonidin-3-glucoside (26.24 ± 0.57, 21.18 ± 1.07, and 24.53 ± 1.33 kJ·mol–1), cyanidin-3-glucoside (16.10 ± 0.96, 11.61 ± 0.74, and 13.34 ± 1.72 kJ·mol–1), and pelargonidin3-rutinoside (8.91 ± 0.17, 7.39 ± 0.98, and 8.23 ± 1.72 kJ·mol–1) of the control sample, calcium carbonate and calcium citrate respectively. The results showed that the addition of calcium salt had a statistically significant (P ≤ 0.05) effect on the degradation of anthocyanins. [ABSTRACT FROM AUTHOR]