UC Davis

Most wine fermentations are completed in successive batches during a 2 month harvest period. Red wine fermentations are usually completed in 10 to 14 days, while white wine fermentations are completed in 21 to 24 days. The demand for resources—equipment, water, energy, labor, etc.—in a short time motivates the precise, automated control of the fermentation process. While the effects of temperature on wine chemistry are well studied, few advanced control strategies have been developed for the precise control of temperature for wine chemistry research. In this study, a nonlinear model predictive controller (NMPC) was developed to determine the temperature to achieve the desired fermentation rate. The controller was combined with a pulse cooling and heating strategy to improve the energy efficiency of temperature control. The feasibility of this approach is demonstrated by simulations and experiments in 15 L fermentations.