Non isothermal phenomenological model of an enological fermentation: modelling and performance analysis

PABLO M. ABALLAY; GUSTAVO SCAGLIA; MARTHA D. VALLEJO; OSCAR A. ORTIZ

Braga Portugal

Congreso; 10th International Chemical and Biological Engineering Conference- CHEMPOR 2008; 2008

The grape juice fermentation constitutes the core of the winemaking process. In this stage, complex physical, chemical and biological changes occur. Also, the presence of nonconstant parameters and high non-linearities produce complex dynamic responses of the bioprocess. In this work, a non-isothermal phenomenological model for a batch alcoholic fermentation is proposed. The model predicts the main process state variables: viable cells, substrate (sugar) and ethanol concentrations, carbon dioxide released, and the bioreactor temperature. It is based on the model developed by Scaglia et al. (2008) which is excellent for isothermal fermentations. In this case, the main model objective has been posed on temperature, due to its control is critical to produce high quality wines and to reduce the winery cooling requirements. The model combines mass and energy balances coupled by the Arrhenius equation that describes the temperature influence on the cell growth rate. Due to the temperature inside the bioreactor must be maintained at 23±1 ºC to avoid the quality product decrease, a wide performance analysis with the model proposed was carried out. The obtained results from simulation show acceptable agreement with own experimental and published data. Therefore, the acceptable model performance will allow its application in advanced optimization and control strategies. product decrease, a wide performance analysis with the model proposed was carried out. The obtained results from simulation show acceptable agreement with own experimental and published data. Therefore, the acceptable model performance will allow its application in advanced optimization and control strategies. for isothermal fermentations. In this case, the main model objective has been posed on temperature, due to its control is critical to produce high quality wines and to reduce the winery cooling requirements. The model combines mass and energy balances coupled by the Arrhenius equation that describes the temperature influence on the cell growth rate. Due to the temperature inside the bioreactor must be maintained at 23±1 ºC to avoid the quality product decrease, a wide performance analysis with the model proposed was carried out. The obtained results from simulation show acceptable agreement with own experimental and published data. Therefore, the acceptable model performance will allow its application in advanced optimization and control strategies. product decrease, a wide performance analysis with the model proposed was carried out. The obtained results from simulation show acceptable agreement with own experimental and published data. Therefore, the acceptable model performance will allow its application in advanced optimization and control strategies. et al. (2008) which is excellent for isothermal fermentations. In this case, the main model objective has been posed on temperature, due to its control is critical to produce high quality wines and to reduce the winery cooling requirements. The model combines mass and energy balances coupled by the Arrhenius equation that describes the temperature influence on the cell growth rate. Due to the temperature inside the bioreactor must be maintained at 23±1 ºC to avoid the quality product decrease, a wide performance analysis with the model proposed was carried out. The obtained results from simulation show acceptable agreement with own experimental and published data. Therefore, the acceptable model performance will allow its application in advanced optimization and control strategies. product decrease, a wide performance analysis with the model proposed was carried out. The obtained results from simulation show acceptable agreement with own experimental and published data. Therefore, the acceptable model performance will allow its application in advanced optimization and control strategies. ±1 ºC to avoid the quality product decrease, a wide performance analysis with the model proposed was carried out. The obtained results from simulation show acceptable agreement with own experimental and published data. Therefore, the acceptable model performance will allow its application in advanced optimization and control strategies.