Concept Development of Soluble Gas Stabilization Technology through a Multidisciplinary Approach Product Development, Experimental Design, Numerical Simulations and Sustainability

Summary

The growing global population and rising demand for food have placed immense pressure on food systems to reduce waste and enhance distribution efficiency. Extending the shelf life of perishable food products is a crucial strategy in addressing these challenges. Soluble Gas Stabilization (SGS) is an emerging food preservation technology that pre-saturates food products with carbon dioxide prior to packaging, leveraging its bacteriostatic properties to inhibit microbial growth and spoilage mechanisms. While SGS has demonstrated significant potential in laboratory environments for prolonging shelf life and maintaining food quality, its industrial-scale implementation remains limited due to process inefficiencies, a lack of systematized development frameworks, and insufficient modeling tools. This research addresses these challenges through a comprehensive approach designed to develop the SGS technology from experimental concept toward practical application. A structured Systems Engineering methodology was employed to manage development complexity and define a set of high-level requirements guiding the design and concept development of SGS systems. First, a sustainability assessment tool, adapted from the recognized Sustainable Development Analytical Grid (SDAG), was developed to evaluate existing food processing equipment from stakeholder perspectives. Applied in a case study, the tool enabled the identification and prioritization of key sustainability objectives across environmental, economic, social, and future-proof dimensions. Results indicated that future-proofing aspects, including risk management, technology resilience, and innovation, were of highest stakeholder concern, followed by time and economic efficiency, as well as safety and social responsibility. To assess the future-proof potential of SGS and its integration with conventional food preservation treatments, this study reviewed and categorized the impacts of combining SGS with both thermal and non-thermal processing technologies. Findings confirm that such combinations enhance bacteriostatic effects and preserve product quality, though the effectiveness depends heavily on specific product characteristics, treatment protocols, and microbial composition. Furthermore, to support optimization and scale-up efforts, a predictive numerical model was developed to estimate the effective diffusivity of carbon dioxide in muscle tissue, treated as a porous medium. The model accounted for structural properties such as porosity, tortuosity, and total liquid fraction—including water and fat—and was validated on pre-rigor top loin salmon tissue. Analysis revealed that diffusivity was not significantly affected by temperature within the tested range of 1◦C to 4◦C at an average initial pressure of 160 kPa (p-value = 0.451). However, it was influenced by the gas-to-product volume ratio and diffusion distance, with potential enhancement from convective effects at the gas–liquid interface. These findings provide valuable insights into the mass transfer mechanisms that underpin SGS performance. Finally, to address the limitations of SGS processing, an alternative continuous gas-flow setup was proposed and experimentally validated. This system utilized low-temperature turbulent CO2 flow to maintain consistent saturation conditions and improve mass transfer efficiency. Comparative simulations demonstrated that the gas-flow setup offered similar performance to static setups over short durations (1-hour treatments), but showed superior performance over extended durations, supporting its potential for industrial application. In conclusion, this dissertation contributes a robust foundation for the development and optimization of SGS technology, offering tools, models, and strategies to facilitate its transition from laboratory innovation to industrial practice. By enhancing food preservation capabilities, this work aims to reduce food waste, increase supply chain resilience, and support global sustainability objectives.