HPSEC with component analysis of citrus and apple pectins after hollow fiber ultrafiltration

Component analysis of high performance size-exclusion chromatograms was applied to 3.3 X concentration of citrus and apple pectins in dilute solution by ultrafiltration with a hollow fiber module fitted with a 100K membrane. Viscosities of the pectins in retained solutions were unchanged and for citrus pectin there was a 10% reduction of weight fraction of the largest-sized component at the last stage of concentration. A small proportion of apple pectin (radius of gyration = 7 nm) was recovered from one permeate by freeze-drying, and, when redissolved in water, produced large aggregates (z-average diam 100 nm, measured by dynamic light scattering). Results can provide guidelines for use of the method during industrial pectin processing