The composition of cell walls from grape marcs is affected by grape origin and enological technique

The grape marc obtained after vinification could be a source of high value compounds and the different winemaking techniques could influence such compounds. The composition of skin cell walls from Monastrell grapes grown in three different locations near Murcia (S.E. Spain) has been studied. The grapes were winemaked with three different techniques (cold pre-fermentative maceration, β-galactosidase enzyme addition and enzymatic preparation addition) and the marc skin cell walls were studied to determine their composition. The results suggest that terroir influenced the percentage of grape skin, the amount of cell wall material isolated from the grape skin, the carbohydrate composition of the cell wall material, and the lignin and protein content of the cell wall material from grape skin. A similar trend has been found within the influence of terroir on cell wall material isolated from the skin separated from the marc, being the differences also due to the enological technique.