The Influence of Wine Components on the Spontaneous Precipitation of Calcium L(+)-Tartrate in a Model Wine Solution

¹ School of Chemistry, The University of Melbourne, Parkville 3052, Australia
² The Australian Wine Research Institute, Waite Road, Urbrae 5064, Australia.

A model wine solution has been used to examine the ability of various components in wine to influence the spontaneous precipitation of calcium tartrate. An increase in ethanol concentration leads to a significant decrease in the induction period. At addition rates of 2 g/L, the order of inhibition shown by the wine organic acids was found to be citric > malic > lactic > succinic. Malic acid causes a 16-fold increase in the induction period for calcium tartrate crystallization compared with only a four-fold increase by lactic acid. The implications of these observations for calcium tartrate stability, especially in sparkling wines, is discussed. Amino acids which have a carboxyl or an hydroxyl group in the side chain, as well as proline, did not affect calcium tartrate precipitation. From the relative ability of the organic acids and amino acids to inhibit the calcium tartrate crystallization process, the structural requirements for an effective inhibitor have been determined.

Key words: calcium tartrate, spontaneous precipitation, crystallization, organic acids, amino acids, malolactic fermentation

Submitted on September 26, 1994