Suitability of solid phase extraction and flame atomic absorption spectrometry for manganese partitioning in red wines

A suitability of a tandem column assemblage comprising a non-ionic adsorbing resin Amberlite XAD-16 and a strong cation exchange resin Dowex 50W-x8-200 linked in a series for the fractionation of Mn in wine was evaluated. Sorption and desorption properties of both sorbents towards simple ions of Mn(II) and its complex ions with citric and tannic acids were preliminary examined. The partitioning of Mn in wine was investigated using a solid phase extraction procedure developed and it resulted in classification of phenolic bound, cationic and residual fractions of Mn. It was found that in red bottled wines analysed Mn is predominantly present in the forms of cationic species, likely to be simple ions and complex ions with low molecular weight hydroxy acids. This fraction of a mean donation of 80% was assumed to be the most bioavailable.