ASSESSMENT OF EXTRACTION PROCESSES, COLOR PROPERTIES AND DEGRADATION KINETICS OF ANTHOCYANIN FROM RED AMARANTH (Amaranthus gangeticus)

Abstract

There is a growing attention in natural colorants as an alternative of synthetic colorants which have many biological activities and antioxidant potential on consumer health. The present study deals with the assessment of extraction process and the effects of pH (1, 3, and 5), extraction media (water and 50% ethanol) and storage condition (ambient and refrigerated) on anthocyanin content, color values as well as degradation kinetics of total anthocyanin in red amaranth. Maximum amount of anthocyanin content was obtained in water and 50% ethanol (41.16+1.91 and 36.3840.28 mg/100g) at pH-3 followed by pH-1 and pH-5. Better results for thermal degradation parameters ( ti, %R) and hunter color values (L*, a*, b*, AE) was noticed at lower pH for water followed by 50% ethanol at refrigerated temperature. Anthocyanin degradation was accelerated at ambient atmospheric temperature (30+2°C) than in refrigerated storage condition (4°C). P", storage time and temperature affected the stability of anthocyanin. Experience of this research work suggests that anthocyanin from red amaranth may be an excellent source to meet up the increasing need of natural colorants.