InsideFood: X-ray CT for quantitative food microstructure engineering

Many food products are microstructured, meaning they contain structural features (such as bubbles, air inclusions, cells and cell walls) that are manifested over a large range of dimensions, including the submicrometer range. To make significant advances in delivering foods with excellent quality the aim of InsideFood was to understand the role of microstructure, and its interactions with composition and external conditions. Controlling and designing new microstructures can only be achieved by first developing accurate techniques that detect changes in the internal structure of foods. For the InsideFood project, we used diverse food systems (Fig.1): sugar foam, fresh apple, crisp bread and created distinct microstructures, in particular by altering the air phase. These foodsystems were studied by using different sensory technologies. In this study, we wanted to characterise these microstructural changes using high-resolution X-ray CT. X-ray CT was very effective for imaging the microstructure of these differing food products. The distinct phases of the foods (solid matrix and air spaces) could be segmented due to a high contrast in X-ray absorption, enabling extraction of 3D geometrical information. X-ray Micro-CT is an exciting tool in food and postharvest technology to study quality of foods at high resolutions. The micro-CT data presented a detailed structural insight into the food microstructures. Moreover we managed to link the microstructure to texture measurements and physiological phenomena. Now we have measured microstructure, the next step would be to control or even design foods based on this information by e.g. predicting longterm storage capacity of fruits or realize novel food concepts in high-tech food processing environments.status: accepte