| Abstract
| - Monovarietal white wines from Maria Gomes and Bical Portuguese Bairrada varieties were preparedaccording to different maceration and pectic enzyme clarification procedures. The polysaccharide-rich extracts, obtained by wine concentration, dialysis, and lyophilization, were fractionated by gradedethanol precipitation. A wide range of fractions rich in polysaccharides were obtained. Using thespectral region between 1200 and 800 cm-1 of the FTIR spectra of the wine polysaccharide dryextracts, using PCA and CCA chemometric methods, it was possible to discriminate the extracts onthe basis of their polysaccharide composition. Moreover, it was possible to identify the wine-makingprocesses involved and their influence on the wine polysaccharides. Furthermore, a calibration modelusing a PLS1 was proposed for the quantification of mannose in the samples obtained by precipitationwith 60% ethanol aqueous solutions. This information will allow an expeditious assessment andmonitoring of the polysaccharide composition and modifications that occur during the wine-makingprocessing and evolution. Keywords: FTIR spectroscopy; wine polysaccharides; mannose; multivariate analysis
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