Protective colloids in traditional-method sparkling wines: effects on chemical composition, sensory properties, and tartrate stability

Abstract

Tartrate precipitation (potassium hydrogen tartrate, KHT, and calcium tartrate, CaT) is a major source of wine instability, particularly concerning sparkling wines, where it may induce gushing. While cold stabilization is effective, it is energy-intensive, whereas protective colloids offer a more sustainable alternative. An unstable Chilean Chardonnay base wine was divided into eighteen 10-L containers and subjected, in triplicate, to six treatments: untreated control, cold stabilization (0 °C for 7 days), carboxymethylcellulose (CMC, 7.5 g/hL), potassium polyaspartate (KPA, 10 g/hL), arabic gum (AG, 25 g/hL), and purified mannoprotein (MP, 20 g/hL). Two weeks later, sparkling wines were produced by the traditional method by adding tirage liqueur (to reach 20 g/L sugar, 2 g/hL bentonite, and ~10⁶ yeast cells/mL; Lalvin EC1118™), bottled, and placed horizontally at 18–20 °C. After six months of lees aging, tartrate potential stability, general chemical composition, color, volatile profile, and sensory attributes were evaluated. Cold-treated wines exceeded the KHT instability threshold according to the mini-contact test, likely due to increased alcohol from secondary fermentation. AG and MP wines were at the threshold, whereas CMC- and KPA-treated wines were stable. Potential CaT instability [1] differed significantly (p<0.05) only between untreated and MP wines, which showed the lowest and highest stability, respectively. No differences were observed in main chemical parameters, although MP wines showed lower pH than AG wines (p<0.05). KPA wines exhibited lower lightness (L*) and higher absorbance at 420 nm, while cold-treated wines showed the lowest yellowness (b*) and absorbance at 420 nm. Thirteen of 36 volatile compounds (SPME-GC-MS) differed among treatments (p<0.05), with acetate esters showing the greatest variation and lowest levels in CMC wines compared with cold-treated ones. Aging-related compounds (vitispiranes) were highest in KPA and lowest in untreated wines. Sensory analysis rating 12 attributes considering visual, aromatic, and in-mouth perception revealed bakery notes (p<0.002), fruitiness (p<0.013), and aromatic intensity (p<0.017) as the most discriminant attributes, with MP and AG wines scoring higher for bakery notes and CMC and MP wines for fruitiness. Overall, tartrate stabilization strategies of base wine significantly influenced wine stability, volatile composition, and sensory perception of the resulting sparkling wines.

References

1. Abguéguen, O.; Boulton, R. (1993). The crystallization kinetics of calcium tartrate from model solutions and wines. Am. J. Enol. Vitic., 44(1), 65-75.