INFLUENCE OF COPIGMENTATION ON THE STABILITYOF SPRAY DRIED ANTHOCYANINS

Anthocyanin rich extracts from several fruits and purified anthocyanins are frequently applied as food colorants, due to the growing awareness of consumers concerning synthetic food additives. Nevertheless, these natural pigments often show poor stability and alongside a rapid loss of coloring properties. A suitable approach for encapsulating and stabilizing of anthocyanin extracts is spray drying. The effects of added copigments (rutin and ferulic acid) on the storage stability of spray dried anthocyanins from blackberry were investigated. Modelling of the degradation kinetics revealed that degradation during storage under light and different temperatures all showed first order kinetics whereby light had a greater impact on anthocyanin stability than elevated temperatures. The addition of copigments led to considerably higher anthocyanin stability compared to samples without copigments and to increased half-life values of the obtained powders regarding color properties. This stabilizing effect may be attributed to the antioxidative properties of the copigments and prevention of the hydration of the anthocyanins during the spraying process. The observed color changes did not correlate with the anthocyanin loss, assuming that degradation of anthocyanin did not only lead to the formation of colorless products but also evoked colored derivatives and polymers.