Extraction of purple corn (Zea mays L.) cob pigments and phenolic compounds using food-friendly solvents

The PCC extract obtained by water-ethanol ratio around 1:1 (40%-60% ethanol) achieved highest yield of monomeric anthocyanins (>13.5 mg/g FW) with low polymeric color, comparable to 70% acetone (14.3 mg/g FW). The amount of PCC monomeric anthocyanin and phenolics recovery extracted with different water-ethanol combination could be predicted using quadratic models (R2 = 0.94 and 0.95). The solvent acidity seemed to impacted water PCC extraction but not much in 70% acetone extraction. This study provides valuable reference information to extract pigments from PCC for potential food application, as synthetic red dye alternatives.