Impact of acidification at bottling by fumaric acid on red wine after 24 months

Global warming is directly linked to a lower concentration of organic acids in grape berries. Because of this lack of organic acids, wines tend to have higher pH levels and low titrable acidity. Many important factors are impacted, such as the chemical, microbiological and organoleptic equilibriums. It is common practice to acidify the wine in order to prevent these imbalances that can lead to wine defects and early spoilage. Tartaric acid (TA) is most commonly used by winemaker for wine acidification purposes. As a potential acidification candidate, fumaric acid (FA), authorized by the OIV in its member states for the inhibition of malolactic fermentation, could also be used since it has a better acidifying power than tartaric acid. Thus, the objective of the present study was to investigate the impact of the addition of FA at bottling in comparison to TA on white wine’s quality. For this purpose, a sulfite-free Cabernet Sauvignon red wine was divided into two batches, one of which was sulfited at 80 mg/L. The two batches, sulfite-free and sulfited, were then redivided into five batches, one of which without any addition, two of the batches in which TA was added at concentrations of 1.25 and 2.5 g/L respectively, and two batches in which FA was added at concentrations of 1, and 2 g/L, respectively. Classical oenological parameters (pH, titratable acidity), color parameters (color intensity, CIELAB), total phenolic compounds (IPT, Folin), as well as total tannins, total anthocyanins and their composition (HPLC analysis) were analyzed. Sensory analyses were also performed on the wines in order to assess the organoleptic impact of FA addition.