Emulsifiers Extracted from Winery Waste

Hydrocolloids were extracted from the alcohol insoluble solids of defatted, finely crushed and freeze-dried winery waste of the Greek variety Xinomavro , using temperature-controlled aqueous solutions buffered at pH 5, pH 7 and pH 9. The extracts were characterized in terms of their macromolecular populations distribution using size exclusion chromatography; of their generic chemical composition and homogeneity using Fourier-transform infra-red (FTIR) spectroscopy and micro-FTIR mapping; of their polymeric particle distribution using dynamic light scattering; and of their charge using zeta potential measurements. These were compared with extracts obtained from fresh grape. The capacity of the extracts toward emulsification and emulsion stabilization was studied at neutral and acidic conditions (pH 7 and pH 3) using light diffraction for droplet distribution measurement and confocal microscopy. The extracts show potential for use as emulsifiers for acidic and neutral model emulsions.