Comparison of the stability of pelargonidin-based Anthocyanins in strawberry juice and concentrate

Strawberries were processed into juice (8degrees Brix) and concentrate (65degrees Brix) and different lots were fortified with pelargonidin 3-glucoside, pelargonidin 3-sophoroside, and acylated pelargonidin 3-sophoroside 5-glucoside. Changes in pigment concentration, color (CIE L*a*b*) and ascorbic acid content were monitored during storage at 25 degreesC. Anthocyanin and ascorbic acid degradations followed 1(st) order reaction kinetics. Fortification increased the half-life of the pigments from 3.5 to 5 d in concentrate and from 5 to 12 d in juice. The half-life of ascorbic acid was 2 d in juice samples and ranged from 3 to 10 d in concentrate samples. Both systems showed changes in chroma and hue angle, but maintained L* values.