Shape morphing of food: Designed surface grooves induce controlled 2D-3D-4D shape changes in a pea protein-based product during drying and frying conditions

Morphing food is a novel approach to controlling dynamic shape change in food, enhancing human-food sensory interactions and fostering sustainability by increasing packaging load saturation and reducing environmental impacts. In this context, this study aimed to investigate groove-induced shape morphing in a pea protein-based product under controlled drying and frying conditions. A pea protein isolate dough (60:40, w/w with water) was sheeted to 5 mm and stamped with 1 mm, 2 mm, and 3 mm grooves using 3D-printed polymer molds. Samples were dried at 45 °C, 55 °C, and 65 °C for 240 min or fried at 210 °C for 30 sec. Higher drying temperatures increased moisture drying rates, with grooved samples reaching up to 7.5 kg water/kg solid. min. At 65 °C, grooved samples showed maximum shrinkage (0.60) and porosity (0.51). The deeper grooved samples (d=3 mm) achieved controlled bending morphing, with a bending angle of 205 ± 2.23° and curvature of 0.267 µ mm⁻¹ . Frying also induced distinct morphing effects, with outward bending of 154 ± 8.98°. Larger groove angles (45°) resulted in twisting morphing during processing. SEM imaging revealed notable surface modifications, while NMR analysis indicated accelerated water loss and microstructural transitions in grooved samples, highlighting the potential of surface grooving for achieving controlled shape transformations in personalised food design and sustainability applications.