Determining Extraction Efficiency and Betalain Pigment Stability of Red Beetroot

Recently, there has been much attention to use of natural pigments as food colorants and healing components. Red beetroot is rich in betalain pigments. In this research, the effect of different solvents (water, water: ethanol: citric acid ratios (60: 40: 0) and (60: 38.5 :1.5)v/v and ascorbic acid concentration (in two levels of 0 and 0.05%)w/v on the extraction efficiency were studied. Betalains were extracted from red beetroot and encapsulated with different encapsulating agents including: maltodextrin (MD) with extract (ER) (20g: 100ml), gum arabic (GA) with extract (20g: 100ml) and maltodextrin+ gum arabic with(ER) (10g: 10g: 100ml) w/v (as encapsulating agents) and then were dried using the freeze dryer. Effect coating agents were studied on the betalain stability. The results showed that various solvents have different effects on the extraction efficiency. Pure water and ethanol: citric acid as solvent, showed the highest (68%) and lowest (7.6%) extraction efficiency, respectively . Ascorbic acid increased the stability of all betalain samples, but it had greatest impact on water extracts and water - ethanol (p<0.05). Effect of different encapsulating agents were studied on the betalain stability. Encapsulated betalains with gum arabic and maltodextrin showed more recovery efficiency than the non- encapsulated betalain sample (as control).