Abstract

In this study, the textural mechanics of strawberry tissues were analyzed using a uniaxial compression test at six temperature  levels,  and  a  dynamic  finite  element  model  of  the  strawberry  drop  system  was  developed  to investigate the collision-damage sensitivity of the fruit. The strawberry geometric model included two parts of the receptacle: the cortex and the pith. The fruit finite element model with average tissue mechanical data was found  to  be  capable  of  reproducing  four  key  collision  mechanical  parameters  (maximum  impact  force  and contact area, drop damage area, percentage of damage volume) with an average relative error of 1.76%, 8.45%, 2.99% and 4.74%, respectively. Five covariance analysis models also showed that the drop direction was the most important factor affecting the occurrence of the fruit drop damage, followed by fruit temperature and drop height. Specifically, in a low temperature range (1 ~ 7 ◦C), the fruit collision damage degree did not change significantly with temperature change, but when the temperature was between 14 ◦C and 35 ◦C, the damage area and percentage of damage volume increased by 0.82 mm2 and 0.06%, respectively, for every 1 ◦C increase in temperature. Furthermore, it was found that there is a strong linear correlation between internal and surface damage in the strawberry fruit, and the obtained mathematical models can be utilized to predict the internal damage  degree  of  fruit  based  on  the  surface  damage  area.  This  study  incorporated  dynamic  finite  element technology  with  statistical  analysis  to  provide  a  systematic  approach  for  investigating  the  collision-damage sensitivity of fresh fruit in relation to fruit temperature.