Effects of High Temperatures on the Efficacy of Potassium Polyaspartate for Tartaric Stabilization in Wines

Potassium polyaspartate (KPA), a colloidal additive for tartaric stabilization, has recently been approved for use in wine (OIV/OENO 543-2016) and has been adopted by many wineries in Europe. Previous research has highlighted its efficacy for tartrate stabilization, which is similar to that of other additives such as metatartaric acid (MT) and carboxymethylcellulose (CMC). However, unlike CMC and MT, KPA has been reported to not affect color or cause haze formation, and to maintain its effect over time. In the present study, we evaluated for the first time the efficacy of KPA in wines treated with different KPA concentrations at high temperatures. A full factorial experimental design was used to investigate the effects and interactions of temperature, storage time, and the dose of KPA on tartaric stability in red and white wines, as evaluated by a conductivity test. The results of this study showed that storage temperature is the variable with the greatest influence on the efficacy of KPA. However, KPA was still able to maintain its efficiency for at least 45 days at temperatures ~40°C, conditions that can sometimes occur during commercial shipment. The results obtained from the conductivity test were consistent with those from a cold test used as a control for measuring tartaric stability.