Exogenous CO₂ in South American sparkling wine

¹ Instituto Brasileiro do Vinho (IBRAVIN). Alameda Fenavinho, 481, ed. 29 ; 95700-000, Bento Gonçalves, RS, Brasil
² Laboratório de Referência Enológica Evanir da Silva (LAREN). Av. da Vindima, 1855 ; 95084-470 Caxias do Sul, RS, Brasil
³ Universidade de Caxias do Sul (UCS), Instituto de Biotecnologia ; Rua Francisco Getúlio Vargas, 1130 ; 95070-560 Caxias do Sul, RS, Brasil

Abstract

The sparkling wine production and consumption have increased significantly in the last years. With the increased demand appear the necessity to check the sparkling wine authenticity, because the practice of adding CO₂ in sparkling wine is not allow. A way to control the carbonation process is through the determination of CO₂ δ¹³C, because the sugar added during the second fermentation define the CO₂ isotopic value, according to elaboration process. For this reason, the aim of this study was to evaluate the relationship between values of δ¹³C from still wines and sparkling wines, in order to set up limit values to exogenous carbonation control. Thirty-eight still wines elaborated by microvinification and 59 samples of commercial sparkling wines were analyzed, using an isotope ratio mass spectrometer (IRMS). The most negative value of natural δ¹³C from still wine found was − 24.7‰, it can be to estimate that lowest values are an indicative of industrial CO₂ addition. Among the commercial sparkling wine from South America evaluated in this study, 10% from the samples showed signs of carbonation. Through this research was possible to establish limits of isotopic values to determine the presence of exogenous CO₂.