Modulating analytical characteristics of thermovinified Carignan musts and the volatile composition of the resulting wines through the heating temperature

The impact of two temperature levels (50 degrees C and 75 degrees C) and heating times (30 min and 3 h) on the composition of thermovinified musts and wines from Carignan was investigated at the laboratory scale in 2014 and 2015. The heating temperature had a significant impact on the extraction of amino acids and a probable thermal degradation of anthocyanins was noted at 75 degrees C. In 2014, musts from grapes that underwent a heat treatment at 50 degrees C for 3 h had a similar level of phenolic compounds as those treated at 75 degrees C for 30 min. This indicates that the reduction of the heating temperature in some vintages can be compensated for through an extension of the heating period. Several grape-derived molecules were impacted by the rise in temperature and wines made from grapes treated at 50 degrees C in most cases contained larger concentrations of geraniol, beta-citronellol, beta-damascenone and 3-mercaptohe xanol.