Energy optimization of the Martinotti-Charmat refermentation process in sparkling wines production

Energy efficiency has become a key focus for the wine industry, as it plays a crucial role in promoting sustainability and meeting ambitious global climate targets. Within a life cycle assessment framework, energy demand during the production phase stands out as a critical lever for wineries - one of the few where they can directly intervene to drive significant improvements in environmental performance. This makes energy optimization not just a necessity, but a strategic advantage for the future of the sector. While numerous studies have examined the topic of energy efficiency from a technological standpoint, there is a notable absence of research exploring the production process. This study deals with the evaluation of the energy optimization of the Martinotti-Charmat secondary fermentation process in the production of sparkling wines, in particular Prosecco DOC. Following an analysis of the process from an oenological perspective, the chemical and physical constraints associated with potential modifications aimed at reducing refrigeration energy requirements are investigated. Furthermore, an energy model of the process was developed to assess the potential benefits of alternative temperature control strategies for critical process steps, namely wine cold tartaric stabilization and subsequent storage prior to final bottling. Different scenarios for the management of these steps were simulated. The results demonstrate the feasibility of significantly reducing process energy requirements while maintaining wine quality through novel temperature control strategies, thus paving the way for improving the sparkling wine production sector in terms of energy and environmental sustainability.