EXTRACTION AND PHYSICOCHEMICAL CHARACTERIZATION OF PECTIN FROM SUNFLOWER HEAD RESIDUES

Pectin was isolated from sunflower head residues, using 0.75% sodium hexametaphosphate extraction followed by acid precipitation. The yield of pectin was7.3% of the head residues. The isolated pectin contained 89.2% anhydrogalacturonic acid, 2% acetyl ester, and 4.2% neutral sugars, which were mainly rhamnose and glucose. The degree of methylation was 38.5%. The pectin had a high viscosity (527 cp at 1% level) at pH 3 and a high water-holding capacity (57g water/g organic matter). The peak molecular mass of the sunflower pectin was >523,000 daltons.