Tentative identification of polar and mid-polar compounds in extracts from wine lees by liquid chromatography-tandem mass spectrometry in high-resolution mode M. P. Delgado de la Torre, a,b,c F. Priego-Capote a,b,c * and M. D. Luque de Castro a,b,c *

Sustainable agriculture has a pending goal in the revalorization of agrofood residues. Wine lees are an abundant residue in theoenological industry. This residue, so far, has been used to obtain tartaric acid or pigments but not for being qualitativelycharacterized asasource ofpolarand mid-polarcompounds such asflavonoids,phenolsand essentialaminoacids.Lees extractsfrom 11 Spanish wineries have been analyzed by liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS) inhigh resolution mode. The high-resolution power of LC–MS/MS has led to the tentative identification of the most representativecompounds present in wine lees, comprising primary amino acids, anthocyans, flavanols, flavonols, flavones and non-flavonoidphenolic compounds, among others. Attending to the profile and content of polar and mid-polar compounds in wine lees, thisstudy underlines the potential of wine lees as an exploitable source to isolate interesting compounds. Copyright © 2015 JohnWiley & Sons, Ltd.Keywords: Wine lees; mass spectrometry; oenology; phenolic compounds; amino acids