Chelation of aqueous iron(III) by 2-acetyl-1,3-cyclohexanedione and beer ageing

Metals in alcoholic beverages: A review of sources, effects, concentrations, removal, speciation, and analysis

“…In doing so, it may induce their deprotonation and thus contribute to changes in beer quality during ageing (Blanco et al, 2003).…”

“…Metals can be present in beer as cations (e.g., Mn 2+ ) or as complex anions (e.g., Fe(III) with cyclic triketones) (Blanco et al, 2003). Strong interactions between the metal cations and ligands in alcoholic beverages are believed to play a key role in some properties of the final product (Blanco et al, 2003).…”

Potential impact of medium characteristics on the isomerisation of hop α-acids in wort and buffer model systems

“…According to Blanco, Caballero, Rojas, Gomez, and Alvarez (2003), Fe 3+ may even induce deprotonation of certain triketones, including bitter acids. This may offer a reasonable explanation for the very high isomerisation yield obtained in wort upon Fe 3+ addition, since the rate limiting step of the overall reaction is considered to be the formation of the anion in the b-triketo system (Jaskula et al, 2008).…”

Chemical fractionation of Cu, Fe and Mn in canned Polish beers

“…However, it has been established that the rate of this deterioration is dependent not only on the total Cu and Fe concentrations, but mostly on the type of forms in which these metals are present in beer (Blanco et al, 2003;Svendsen and Lund, 2000;Fantozzi et al, 1998;Ono, 1996, 1999). Both metals form the complex ions with different organic compounds, and indeed, a few known beer components capable of scavenging the reactive oxygen species and capturing the Cu and Fe ions have been shown to inhibit the deleterious effect of O 2 and the promotion of the formation of oxygen radicals (Onate-Jaen et al, 2006;Bamforth, 1999;Fantozzi et al, 1998).…”