“Enological” Metal Speciation Analysis

Electrochemical and theoretical complexation studies for Zn and Cu with individual polyphenols

“…as micronutrients and flavour enhancers, their toxic relevance, i.e. Pb [2] and others for their cationic contribution [5].…”

Atomic spectrometry methods for wine analysis: A critical evaluation and discussion of recent applications

“…Size fractionation of nonvolatile dissolved organic compounds and metal species has been achieved by multistage ultrafiltration coupled to ICPMS, leading to the conclusion that, e.g., most of the Ba and Sr species were found in the lowest molecular fractions (<1 kDa) and most of the Pb species in higher molecular fractions (>1 kDa) [121]. Murányi and Papp used filters of different pore size to investigate which fraction of a particular metal (Cd, Pb, Cu, Zn, Mn, Al, Fe, Ca) can be found in the solution, in colloidal form or in the form of suspension and concluded that the reduction of a specific metal due to filtering shows considerable differences related to former treatment and storage of the wine [122]. Complexation with biological ligands is also receiving attention.…”

Chemical speciation and fractionation of metals in wine

“…The large number of potential complexes makes speciation analysis very difficult. Ultrafiltration has been used for examining the distribution of metals in different particle size fractions (McKinnon and Scollary, 1997;Murányi and Papp, 1998). Enologically the colloidal fraction is very important, because it destroys the quality of wines.…”

“…At concentrations above 10 mgyL iron creates insoluble suspensions which are known as hazes. 60 -87% of iron in Hungarian wines was found in colloid solution as this fraction was removed by filtration through a 0.2 mm-pore-size membrane filter (Murányi and Papp, 1998). Differentiation between insoluble-suspended iron and aqueous iron was proposed using a sequential cloud point extraction procedure (Paleologos et al, 2002).…”