AIM: The use of different tank materials during red wine aging has become increasingly popular, but little is known about their impact on wine chemical and physical parameters. The present study aims to model the evolution of Sangiovese red wine during one-year aging at industrial scale in different tank materials (stainless steel, epoxy-coated concrete, uncoated concrete, raw earthenware amphora, new oak barrel and used oak barrel), in order to describe how the tank material could both allow the mass transfer of different amount of oxygen, or tannins and affect the oxidation and reduction reactions in wine.METHODS: A Sangiovese red wine from 2018 harvest was monitored during one-year aging in six different tank materials in industrial scale (5 hL) and in triplicate. The wine chemical and physical parameters monitored were: dissolved oxygen (DO), redox potential (EH), Cielab coordinates, acetaldehyde, monomer anthocyanins and polymeric pigments content. The tank materials (M), storage time (t) and temperature (T) were considered as factors. Stainless steel (SS) was chosen as reference material. The kinetic models of the collecting data were performed as described in literature when available, otherwise a polynomial curve was adopted to obtain a good phenomenological fitting.RESULTS: The experimental data were modeled and the kinetic models were able to describe the differences between the wine samples aged in the different tank materials. The same equation was used to describe the kinetics of oxygen consumption (DO) and six equations were instead necessary to model redox potential (EH) trend for the wines aged in the different tank materials (1,2,3). The DO and EH were also related to the chemical phenomena which were monitored and modeled for polymeric pigments, monomeric anthocyanins, acetaldehyde, and CIELab coordinates measurements during wine aging (4,5). Through the modeling of the different chemical parameters it was possible to evidence differences between the wines aged in different tank materials. In particular, the tanks in stainless steel and in epoxy-coated concrete were the least suitable to let the variation of the redox state of the wines and consequently to activate the polymerization reaction of wine phenolic fraction, exactly the opposite of the oak barrels; earthenware raw amphorae and uncoated concrete, on the other hand, had an intermediate behavior, but tended to be more similar to oak barrels.CONCLUSIONS: The kinetics modeling of chemical and physical wine parameters was able to describe differences among wines aged in different tank materials. In particular, the one-year evolution of the phenolic composition, dissolved oxygen and redox potential of wines showed significant differences between aging tanks involved, differentiating the wines according to the material.
Authors: Francesco Maioli – Department of Agricultural, Food, Environmental, and Forestry Sciences and Technologies – University of Florence, via Donizetti, 6 – 50144 Firenze (Italy),Lorenzo GUERRINI, Department of Agricultural, Food, Environmental, and Forestry Sciences and Technologies – University of Florence, via Donizetti, 6 – 50144 Firenze (Italy) Monica PICCHI, Department of Agricultural, Food, Environmental, and Forestry Sciences and Technologies – University of Florence, via Donizetti, 6 – 50144 Firenze (Italy) Alessandro PARENTI, Department of Agricultural, Food, Environmental, and Forestry Sciences and Technologies – University of Florence, via Donizetti, 6 – 50144 Firenze (Italy) Bruno ZANONI, Department of Agricultural, Food, Environmental, and Forestry Sciences and Technologies – University of Florence, via Donizetti, 6 – 50144 Firenze (Italy) Valentina CANUTI, Department of Agricultural, Food, Environmental, and Forestry Sciences and Technologies – University of Florence, via Donizetti, 6 – 50144 Firenze (Italy)
Email: francesco.maioli@unifi.it
Keywords: dissolved oxygen, enological tank materials, earthenware raw amphora, redox potential, uncoated concrete, wine aging kinetics
