Advancing in Process Analytical Technology: e-sensing for food cold chain

The PhD research project focuses on developing Process Analytical Technology approaches to enhance refrigeration technologies along the food cold chain. Specifically, it aims at optimizing superchilling in food processing and at addressing cold-induced damage during storage. The project will study physicochemical changes occurring in transformation and conservation by conventional targeted techniques. Furthermore, untargeted techniques, combined with Chemometrics, will be integrated for better understanding and process modelling. Ultimately, the project seeks to extend shelf life, improve product quality, and potentially reduce environmental impact. Food companies will benefit of these advancements, aligning with the principles of Industry 4.0. State-of-the-Art In recent years, the food industry has faced significant challenges from inefficient refrigeration management along the cold chain, resulting in alarming levels of food waste. Studies estimate that approximately 25-30% of the World's food production is lost due to inadequate temperature control, revealing a critical gap in preserving food quality and extending its shelf life (CORDIS project 245288). Temperature control is a crucial factor influencing quality and safety of food products at various stages of the supply chain, from production to distribution and consumption. Fresh produce requires meticulous temperature control to maintain freshness, texture, and nutritional integrity. However, despite ongoing research and development efforts to advance refrigeration technologies, several challenges persist. Current approaches often fail to effectively preserve food quality while minimizing environmental impact. Traditional refrigeration techniques can lead to texture degradation, loss of nutrients and reduction in sensory attributes of perishable foods. Superchilling has emerged as a promising process to extend shelf life while maintaining produce high quality, yet existing systems are not capable of real-time monitoring ( Banerjee and Maheswarappa, 2019). This limitation poses significant obstacles in ensuring consistent and optimal superchilling conditions throughout the cold chain. Indeed, superchilling involves lowering the temperature of the foodstuff to 1–2 °C below its initial freezing point (Magnussen et al., 2008). However, no additional specifications are considered, thus compromising process effectiveness. Furthermore, cold temperature storage, while having the potential to extend shelf life, is not without disadvantages. Cold-induced damage, such as chilling injuries, remains a prevalent concern, particularly for perishable fruits and vegetables. Current protocols to detect and prevent chilling damage are often reactive rather than proactive, resulting in increased food waste and compromised product quality. In this context, the PhD Project will focus on increasing knowledge on superchilling and chilling injuries by conventional approaches and untargeted tools to monitor and optimize superchilling processes and to quickly identify and prevent chilling injury. In detail, the research aims at investigating the application of superchilling to specific food items, including pork loin and potatoes. While existing literature, such as Lee et al. (2023), emphasize the benefit of superchilling in meat preservation, the potential application in potatoes remains relatively unexplored. Conventional approaches will be supported by untargeted techniques (NIR, e-nose, and thermography) for the assessment of texture, colour, water-holding capacity and microbial count in both meat and potatoes. With the goal of developing multivariate control charts for online process monitoring, the research seeks to improve food preservation methods, thereby ensuring product integrity and satisfying consumer demands for quality. Regarding chilling injury, potatoes and kiwi will be considered to further investigate previous findings (Gao et al., 2021; López-Maestresalas et al., 2016), thus gaining a deeper understanding of the complex enzymatic mechanisms underlying cold damage. By integrating NIR, thermography and e-nose, alongside conventional techniques, the research aims at providing a comprehensive characterisation of texture, microstructure, and enzyme activity, advancing the field of cold damage assessment in perishable foods. In conclusion, while ongoing advances in refrigeration technologies, including superchilling and sub-zero storage methods, promise to improve food preservation and reduce food waste, significant challenges remain. By adopting untargeted solutions for in real-time monitoring and by innovative intervention technologies, the food industry will enhance environmental sustainability, efficiency, and product quality throughout the cold chain. 2. PhD Thesis Objectives and Milestones The PhD research project aims at developing process analytical technology (PAT) approaches to improve refrigeration technologies in the food cold chain, extending shelf life, improving product quality, and reducing environmental impact. The superchilling research project aims at studying, by conventional approaches, the main process factors affecting product structure and enzymatic activity. The fundamental knowledge will allow to develop and implement statistical multivariate control charts, based on untargeted approaches, to describe, optimise and monitor the process in real-time. For chilling injuries, protocols to monitor and reduce damage will be developed, and process factors effecting cell structure, enzymatic activity, and oxidative stress will be studied by conventional and untargeted approaches, thus improving cold chain management and real-time quality control. This PhD thesis project will be subdivided into the following activities (WP) according to the Gantt diagram in Table 1: WP1) Superchilling transformation on meat WP2) Superchilling transformation on potatoes WP3) Chilling injury assessment on potatoes WP4) Chilling injury assessment on kiwi WP5) Writing and Editing of the PhD thesis, scientific papers and oral and/or poster communications. Table 1 Gantt diagram for this PhD thesis project. Activity Months 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 WP1) Superchilling - meat 1) Meat processing 2) Quality assessment 3) Model development WP2) Superchilling - potatoes 1) Potatoes processing 2) Quality assessment 3) Model development WP3) Chilling injury - potatoes 1) Potatoes collection 2) Chilling injury assessment 3) Model development WP4) Chilling injury - kiwi 1) Kiwi collection 2) Chilling injury assessment 3) Model development WP5) Thesis and Paper Preparation 3. Selected References Banerjee, R., & Maheswarappa, N. B. (2019). Superchilling of muscle foods: Potential alternative for chilling and freezing. Critical reviews in food science and nutrition, 59(8), 1256-1263. Food Refrigeration Innovations for Safety, consumer Benefit, Environmental impact and Energy optimization along cold chain in Europe (https://cordis.europa.eu/project/id/245288) Gao, M., Guo, W., Huang, X., Du, R., & Zhu, X. (2021). Effect of pressing and impacting bruises on optical properties of kiwifruit flesh. Postharvest Biology and Technology, 172, 111385. Lee, H. J., Kwon, J. A., Kim, M., Lee, Y. E., Ryu, M., & Jo, C. (2023). Effect of supercooling on storage ability of different beef cuts in comparison to traditional storage methods. Meat Science, 199, 109137. López-Maestresalas, A., Keresztes, J. C., Goodarzi, M., Arazuri, S., Jarén, C., & Saeys, W. (2016). Non-destructive detection of blackspot in potatoes by Vis-NIR and SWIR hyperspectral imaging. Food control, 70, 229-241. Magnussen, O. M., Haugland, A., Hemmingsen, A. K. T., Johansen, S., & Nordtvedt, T. S. (2008). Advances in superchilling of food–Process characteristics and product quality. Trends in Food Science & Technology, 19(8), 418-424.