SPECTROSCOPIC STUDY ABOUT THE KINETICS OF THE ANTHOCYANIN PIGMENTS EXTRACTION DURING THE MACERATION OF CHERRIES IN LIQUOR

ABSTRACT

An experimental study of the effect of temperature on the kinetics of anthocyanin pigments extraction during the maceration of cherries (Prunnus avium) into a hard spirit is reported. The analytical method used was UV-Vis spectrophotometry. The initial extraction rate showed an Arrhenius-type dependency, with an apparent energy activation of 18.7±1.2 kcal/mol. Furthermore, a study about the evolution of the color (from colorless to red-orange) during the soaking process was made by calculating the CIE tristimulus values (X, Y, Z) for illuminant C, until to reach the apparent stabilization of color, what occurs after about two weeks for temperatures of 5°C and 23°C, whereas it happens after about four weeks for the other studied temperature (30°C).

Keywords:

• Anthocyanin pigments
• Cherries (Prunnus avium)
• Hard spirits
• Liquor
• Visible spectroscopy
• Color measurement

ACKNOWLEDGMENTS

This work was supported in part by the Laboratory of Applied Chemistry (Química Aplicada), at the Universidad Politécnica de Madrid. The authors also thank the Council of El Arenal (Ávila, Spain) and Ruavieja S.A. for furnishing the cherries and hard spirit, respectively used in this study.