Impact of the fumaric acid/glutathione pair addition before bottling on Cabernet Sauvignon wine quality

Abstract

Over the last decades, climate change and rising temperatures have impacted the wine industry. Wines from warm regions tend to have a higher pH and lower total acidity. This lack of acidity leads to microbiologically unstable wines (1). Because of the high pH values, higher doses of sulfur dioxide (SO2) are needed to protect the wines, which is in contradiction with the wish of consumers to reduce the use of SO2 in wine. Glutathione (GSH) is known for its antioxidant properties and is already used in white wines to help prevent browning and early spoilage signs (2,3). Fumaric acid (FA), in addition to its high acidifying power, can also be interesting for its antibacterial and antifungal properties (4,5). GSH combined with FA (GSH+FA) could be a candidate to help reduce the use of SO2. Thus, the study aims to evaluate the impact of addition at bottling of GSH, by itself and combined with FA on the quality of a Cabernet Sauvignon red wine.
A sulfite free Cabernet Sauvignon wine was split into two batches: one was kept sulfite-free and the other one was sulfited (80 mg/L). In both batches, FA (0 or 2g/L) and/or glutathione (0, 25 or 50 mg/L), were added. Classical oenological parameters (pH, titratable acidity), color parameters (color intensity, CIELAB), total phenolic compounds (IPT, Folin, total anthocyanins and total tannins), antioxidant capacities (DPPH and CUPRAC) were analyzed just after bottling and six months later. Treated wines were compared to the non-sulfited (NS) and sulfited (S) control wines. Sensory analyses were also performed on wines.

References

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