BENCH-SCALE PROCESSING OF RED-COLORED EXTRACTS FROM SUNFLOWER HULLS

Extracts were prepared from the hulls of purple-hulled sunflower, then processed using clarification, evaporation, and spray drying. Additio n of citric acid to solvent or raw extract substantially reduced pigme nt yield, probably by precipitation, but the loss was diminished if ci tric acid addition was delayed until after evaporation or spray drying . The highest overall yield, 1.5 to 1.7 mg spray-dried pigment per gra m of dry hulls, was achieved without addition of citric acid. Pigment loss was observed at each step, and in the case of evaporation, appear ed to result mainly from pigment degradation. Although increased brown ing was observed at each step, reconstituted spray-dried extracts stil l had an attractive red color.