Table 1.

Metabolites detected in grape extracts, using LC-MS in negative or positive ion modes.

Metabolite class	Ionization mode	Metabolites
Sugars	Negative	Sucrose, hexoses, small oligomers
Aminoacids	Positive	-
Flavan-3-ols	Negative and positive	Catechin, epicatechin, procyanidins
Anthocyanins	Negative and positive	Non-acylated anthocyanins, anthocyanins acylated with acetic, coumaric and caffeic acid
Stilbenes	Negative and positive	Resveratrol, resveratrol oligomers, viniferins
Non-aromatic organic acid	Negative	Tartaric, citric, malic acid
Hydroxycinnamic acid derivatives	Negative	Caffeic, coumaric and ferulic acd derivatives, hydroxytirosol derivatives
Hydroxybenzoic acid derivatives	Negative	Dihydroxybenzoic acid, vanillic acid, gallic acid derivatives