Air-Coupled Ultrasonic Inspection of Foods: A Review

Abstract

In the context of the ongoing digital revolution, the food industry grapples with significant challenges concerning quality control, safety, production efficiency, and economic viability. Tackling these challenges requires analyzing a large volume of samples-preferably the whole production-to extract the maximum amount of information, facilitating food processing optimization, quality assurance, safety protocols, and minimizing the energetic impact. Developing monitoring systems for the non-invasive, accurate and real-time measurement of compositional properties, texture, and the detection of foreign bodies throughout the entire production remains a challenge in the agri-food sector. This challenge reflects that these properties affect both quality and food safety but also that current technologies are not capable of monitoring them at an industrial level. Over recent decades, ultrasound technology has garnered significant attention from stakeholders across the food supply chain owing to its potential to revolutionize food industry automation. Ultrasound inspection offers numerous advantages, including the rapid, precise, and cost-effective assessment of product properties, as well as the real-time monitoring of internal quality attributes across various stages of food processing. By interacting with matter, sound waves provide valuable insights into the composition, structure, and physical state of food constituents through changes in velocity, attenuation, and spectral response. This review summarizes recent findings in the use of air-coupled ultrasound inspection for ensuring food quality and safety control.