Replication Data for: Interplay between microstructure deformation, oil absorption, and physicochemical changes to starch during deep-frying

Starch constitutes the major macronutrient constituent in numerous deep-fried foods. In this study, the impact of starch physicochemical properties during deep-frying on the corresponding microstructural deformations were investigated for wheat starch (WS) and potato starch (PS) hydrated to 40 and 50 % moisture content (MC) using complementary techniques assessing (micro)structure in-situ (time-resolved X-ray microcomputed tomography and variable-temperature time domain proton nuclear magnetic resonance) and ex-situ (differential scanning calorimetry, swelling properties and scanning electron microscopy). Within 5 s of deep-frying, WS and PS swelling increased and most starch gelatinized, resulting in fully amorphous starch chains exhibiting high molecular mobility. Structure expansion during deep-frying (5–30 s), triggered by rapid steam generation in pre-existing air pores, was supported by starch chains in a rubbery state. Notably, PS exhibited greater swelling, more extensive disruption of granule morphology, and formed larger pores in the microstructure compared to WS. With longer deep-frying times, WS and PS granular integrity was progressively lost. Expansion of steam-filled pores, and thus global structure, ceased when starch in the outer regions of the structure lost sufficient water and transitioned to a glassy state. Oil absorption during deep-frying strongly depended on the starting porosity of formulations. PS and WS at 40 % MC were highly porous before deep-frying and displayed considerable oil absorption immediately upon their submersion in oil when vapor pressures were still low. However, PS and WS at 50 % MC did not exhibit porous microstructures before deep-frying and showed no oil absorption during the process (60 s).