Sunflower Protein Concentrates and Isolates' Low in Polyphenols and Phytate

Protein concentrates and isolates from sunflower (Helianthus annuus L.), essentially free of polyphenols and/or low in phytate, were prepared from dehulled seeds by a sequential extraction procedure using organic solvents, such as hexane for defatting and acidic butanol for removing polyphenols. Phytate was removed by aqueous extraction and separation at acidic and/or alkaline conditions, depending on the relative solubility of the protein and phytate. Reduced-phytate concentrates and isolates developed off-colors unless the polyphenol concentration was less than 0.05%. The protein solubility profile of the reduced-phytate products was much better than that of the defatted meal, especially below the isoelectric point.