Optimization of extraction of anthocyanins from black currants with aqueous ethanol

Extraction of anthocyanins from black currants using aqueous ethanol was optimized for yield and antioxidant activity. The process variable having the most effect on the extraction was the solvent to solid ratio, which increased phenolic extraction in the whole range from 0 to 19 L/kg. Total phenolics increased with ethanol concentration up to a maximum at about 60% and then decreased with further increase in solvent concentration irrespective of the solvent to solid ratio. Temperature only affected the extraction of anthocyanins. Increasing the temperature beyond 30 to 35 degreesC resulted in degradation of anthocyanins and reduction of yields. Variation in extract composition was not sufficiently large to affect antioxidant activity.