THERMODYNAMIC INVESTIGATIONS OF THE COPIGMENTATION PROCESS BETWEEN CYANIDIN 3-GALACTOSIDE AND GALLIC ACID AT DIFFERENT TEMPERATURES.

The effect of temperature on the stability of anthocyanin extract from aronia as pigment and gallic acid as copigment was presented. The pigment:copigment system was investigated with different concentration from 1:1 to 1:50 molar ratio and at different temperatures at heating (from 25 to 80°C) and cooling (opposite to 25° The thermodynamic parameters of the system, ΔG, ΔH and ΔS were calculated as a function of temperature. Obtained results confirmed that the interaction between pigment: copigment complex was destroyed at heating to 80oC and at following cooling to 25°C reversibility of the copigmentation is observed. Keywords: cyaniding, gallic acid, copigmentation, thermodynamic parameters. [ABSTRACT FROM AUTHOR]