The effects of solid fraction and container pressure on carbonate drinks pasteurization

• The solid fraction increases the nonlinearity of the thermal process • The internal pressure changes the effervescence, reducing or increasing the thermal inertia. • Thermal inertia changes for the heating and cooling process depending on the solid fraction. • Gas and solid fraction change the internal pressure-to-temperature relation. Thermal pasteurization is a food preservation process that deactivates or eliminates bacteria, extending shelf life. Thermal pasteurization is based on the temperature-controlled variation of the food for a specific duration. In this work, three carbonate fluids with different solid contents were tested through a complete thermal pasteurization cycle (mimicking a continuous industrial process using a tunnel machine) under two container conditions: unsealed (ambient pressure) and sealed (pressurized). Based on comparisons between the unsealed and sealed containers, the results show that the trends in the heat transfer coefficient, drink temperature, and internal pressure differ with respect to internal pressure and food solid fraction. Solid content interacts with the gas fraction, making the thermal process difficult to predict and measure using industrial (high-production-rate) methods. Understanding the non-linear behavior of carbonate drinks prepared from homogeneous or heterogeneous substances is fundamental to preserving food quality and ensuring food safety.