Boltzmann-Based Empirical Model to Calculate Volume Loss during Spirit Ageing

• Published in: Beverages (Basel) Vol. 5; no. 4; p. 60
• Main Authors: del Toro del Toro, Noemí, Fong Casas, Fredy, Ayan Rial, Julio, Caridad Portuondo González, Maria, Crespo Sariol, Harold, Navarro Campa, José, Yperman, Jan, Vandamme, Dries, Carleer, Robert
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01-12-2019
• Subjects: ageing; Aging; angel’s share; Basements & cellars; boltzmann equation; Boltzmann transport equation; Empirical equations; Ethanol; Evaporation; Humidity; Mathematical models; Parameters; Relative humidity; Spirits; Variables; volume loss; Cuba
• ISSN: 2306-5710; 2306-5710
• DOI: 10.3390/beverages5040060

The Boltzmann equation is applied to fit data of volume loss for evaporation (in %) during spirit ageing in northern white oak (Quercus Alba) standard barrels of 205 L (+/− 10 L) using a temperature and humidity controlled cellar. The Boltzmann equation satisfactory fitted to the experimental data of the volume loss against temperature at constant humidity. Two parameters of the Boltzmann equation showed a linear dependency on the relative humidity of the air, while the other two parameters exhibited a constant value independently of the air humidity. The found empirical mathematical model can be used to calculate the volume loss for evaporation of spirits (40% v/v of ethanol) during ageing in terms of relative humidity (range: 40%–95%) and temperature (range: 10–30 °C) with significant accuracy.