Loss and Regeneration of Betacyanin Pigments During Processing of Red Beets

ABSTRACT Samples of red beets were analyzed for betacyanin pigment losses during processing by high performance liquid chromatography. Total pigment loss was 41% after canning relative to the pigment content of fresh beets. Blanching to an internal temperature of 66°C caused a 23% loss while sterilization at 126°C for 10 min accounted for a loss of 22% of the pigment content of blanched beets. The betanin‐isobetanin ratio changed with increasing heat treatment. The ratio for fresh, blanched and sterilized beets was 25:1, 9:1, and 2.5:1, respectively. Pigment regeneration after heating was observed in all samples, and was measured in beet juice and purified pigment solutions immediately and after appropriate intervals. Completion of pigment regeneration occurred within 10 hr in beet juice and 2 hr in purified pigment solutions.