Dietary fiber and cell wall polysaccharides from plum (Prunus domestica L.) fruit, juice and pomace: Comparison of composition and functional properties for three plum varieties

• Saccharide composition of pectins in plums and plum pomaces was compared.
• Differences in fruit and pomace dietary fiber were characterized.
• Variability in fiber for cultivars, for fruits and for pomaces is described.
• Plum pomace was found to be an efficient source of functional fiber.

The aim of the present work was to characterize the pectins present in plum fruit, juice, and pomace for three plum varieties, “Promis,” “Najbolja,” and “Dąbrowicka” (all belonging to the species Prunus domestica L.). The content of dietary fiber in the pomace was 5 to 9 times higher than that in the fruit. In turn, the content of soluble fibers and readily soluble pectins (water and chelator soluble pectins) was markedly lower as compared to the fruit, and their hydrodynamic volume was decreased, especially in the case of water soluble pectins. As a result, the hydration capacity of AIS from the pomace was half of that of AIS from the fruit, but its levels were still high enough for it to be used as an ingredient in food products (WBC > 5.5 g/g). Thus, plum pomace could be an efficient source of functional fibers.