H, C, and O Stable Isotope Ratios of Passito Wine

Abstract

In this study we investigated the effect of the grape withering process occurring during the production of Italian passito wines on the variability of the (D/H)I, (D/H)II, δ(13)C, and δ(18)O of wine ethanol and the δ(18)O of wine water. The production of PDO Erbaluce di Caluso Passito in five different cellars in Piedmont (Italy) was considered in two successive years. Moreover, samples of 17 different traditional Italian passito wines taken at different stages of maturation were taken into account. We found that the δ(18)O of must and wine water and the δ(18)O of ethanol decrease in the case of passito wines produced in northern and central Italy using postharvest drying of the grapes in dedicated ventilated or unventilated fruit drying rooms (fruttaio), during autumn-winter. For passito wines produced in southern Italy, where the main technique involves withering on the plant (en plein air), δ(18)O tends to increase. The (DH)I of wine ethanol did not change during withering, whereas the (DH)II and δ(13)C values changed slightly, but without any clear trend. Particular attention must be therefore paid in the evaluation of the δ(18)O data of passito wines for fraud detection.

Wine characterisation according to geographical origin using analysis of mineral elements and rainfall correlation of oxygen isotope values

“…Studies have demonstrated that the 18 O/ 16 O ratio is a useful footprint for wine origin (Perini et al ., 2015; Orellana et al ., 2019; Bononi et al ., 2020) because oxygen is actively involved in the metabolism of the plants and undergoes little fractionation during the process of the plant growth. The climate and location have the strongest relationship with δ 18 O, as oxygen isotope value was positively correlated with oxygen isotope value of water and negatively correlated with precipitation (Camin et al ., 2015).…”

“…These differences can be explained by the average precipitation during the harvest and the altitude of each individual region. There was no difference in oxygen isotope between Italian wine and grape juice, ranging from −2‰ to −6‰ (Perini et al ., 2015). δ 18 O in Washington and California ranges from −3‰ to 5‰ and 2‰ to 14‰ (Orellana et al ., 2019).…”

“…Studies have demonstrated that the 18 O/ 16 O ratio is a useful footprint for wine origin (Perini et al, 2015;Orellana et al, 2019;Bononi et al, 2020) Thus, the stable isotope oxygen is an effective indicator of wine authenticity of origin (Chatzi et al, 2016).…”

“…(1994) have determined oxygen isotope based on the principle of oxygen isotope exchange between wine water and carbon dioxide, and they think it is possible to use this indicator to get origin of wine. In the past ten years, many countries include Brazil, Germany, Italy, Greece and America apply to oxygen isotope technology for identification of wine origin (Dutra et al ., 2013; Monakhova et al ., 2014; Perini et al ., 2015; Chatzi et al ., 2016; Orellana et al ., 2019). In addition, stable isotopes are often combined with mineral elements to identify wine‐producing areas (Dutra et al ., 2013; Dinca et al ., 2016; Orellana et al ., 2019).…”

CHIMALI 2014: Bioactive Metabolites and Contaminants in Fruits and Vegetables

“…2 This investigation was based on flour samples grown with synthetic nitrogen fertilizer animal manure and green manure from atmospheric nitrogen fixing legumes, and the results demonstrate that the molecular amino acid δ 15 N isotope profile is different in samples, depending on the relative source of nitrogen. Perini et al 3 report the use of stable isotope ratio analysis to verify the authenticity of Passito wine. The effect of the grape's withering process on the variability of the (D/H) I , (D/H) II , and δ 13 C of wine ethanol and the δ 18 O of wine water were monitored.…”