Figure 1.

Representation of the loadings (variables) and the scores (skin extracts) in the plane defined by the 1st and 2nd Principal Components (PCA). For each cultivar (blue), the suffix G represents grape extracts, P represents pomace extracts. In red are reported the chemical variables that describe the polyphenolic profile of the extracts: GAE = total polyphenols; TF = total flavonoids; TA = total anthocyanins; MA = monomer anthocyanins; V = flavans reactive with vanillin; P = proanthocyanidins; Tannins = condensed tannins (phloroglucinolysis); mDP = mean degree of polymerization; C, EC, ECG = (+)-catechin, (−)-epicatechin and (−)-epicatechin-3-O-gallate present as terminal units; CP, ECP, ECGP = (+)-catechin, (−)-epicatechin and (−)-epicatechin-3-O-gallate present as extension units; EGCP = (−)-epigallocatechin present only as extension unit; C%, EC%, ECG% = total percentages of the monomers (terminal + extension).