Effect of extraction conditions on colour content from raw beetroot

Abstract

In the present study, a preliminary investigation on extraction and optimization of red colour from raw beetroot has been conducted to optimize the dye extraction process, the extraction parameters, viz temperature is varied from 6 °C to 70 °C, time from 30 min to 120 min and medium pH from 3 to 11. At 45°C temperature, 90 min extraction time and 5 pH, the maximum colour extraction is achieved, i. e. at this optimum condition, the maximum colour yield (2.49 ± 0.08 g/100mL) is obtained. It is observed that at ≥47.5°C, the chromophore of beetroot dye is denatured as can be seen by the value of λ max, which is changed form 530 nm to 430 nm at ≥47.5°C.