Attempted Identification of Causal Constituents of Pink Discolouration in White Wines

The pinking phenomenon has been known in the wine world for past 50 years. phenomenonoccurs when a white turns pink under certain conditions. Since then, Portuguese study foundmalvidin-3-O-glucoside Siria grapes making connection to anthocyanin as causing agent. Control(K), naturally pinked (NP) and induced (PI) Sauvignon blanc samples were analysed by LCMSand WineScanTM (Fourier Transform Infrared – FTIR) after Solid Phase Extraction. monomericanthocyanins pH differential method, CieLab was used differentiate colourdifferences between control samples. It found that malvidin-3-O-glucoside belowthe threshold values facilitate wines. Petunidin-3-O-glucoside showed aslight peak LC-MS analysis, together with malvidin-3-O-glucoside, potential pinkthe wines increased. FTIR results phenols anthocyanins absorption could not bedistinguished there possibly other compounds involved of Analysisby expressed PI darker colour than absorbency valueat 500 nm at least three times higher control, showing aggressive oxidative natureof H2O2 on wine.