Thermo-biomechanical coupling analysis for preventing tomato fruit cracking during ripening

Fruit cracking is closely related to the heat transfer resulting from sunlight, so a thermo-biomechanical coupling three-point bending FE analysis in the tomato pericarp sample was performed. Results showed that the established FE model was capable of reproducing the experimental probe loading force-pericarp deflection and the crack propagation length-pericarp deflection curves in deflection deformation up to 6 mm, with average relative errors of 3.0% and 4.3%, respectively. The propagation area and volume of the crack in pericarp model were gradually sensitive to the temperature gradient acting on the exocarp surface and fruit ripeness. Three obtained linear mathematical models can quantitatively predict the cracking status of the pericarp under different temperature gradient levels when the sunlight caused a uniform temperature increase on the exocarp surface. The tomato had a better anti-cracking ability when the sunlight caused a non-uniform temperature increase on the exocarp surface. This study provides a basis for preventing the cracking of tomato fruit during development by controlling the environment.