Zhiguo Li, Yuqing Wang, Yeming Zhang and Xiaojing Chen
School of Chemical Engineering, University of Birmingham, Birmingham, UK
School of Mechanical and Power Engineering, Henan Polytechnic University, Jiaozuo, China
Scientific Tracks Abstracts: J Food Process Technol
Mechanical characterization of single cells is vital to the macro-scale modelling and simulation of mechanical damage to fruits and vegetables. The mechanical behaviour of single cells in the tomato mesocarp tissue was characterized by micro-compression testing. Single cells of Elegance tomatoes were novel isolated by mechanical brushing from a mesocarp block into water in a beaker and then transferred into a chamber for micro-compression. In order minimise the effect of viscoelasticity and possible loss of water under compression, 20 single cells were compressed to a final deformation of 15% at 4900 μm/s which was much higher than the previous loading speed. The cells were treated as a solid sphere in order to model their elastic behaviour using the Hertz model. The cell geometry was characterized by the initial height, geometric mean diameter and sphericity and the elastic-plastic mechanics of cell were characterized by peak force Fmax, elastic modulus E and yield stress Ï?y deduced by Kogut & Etsion (2002). There was a strong correlation between the initial height and geometric mean diameter, and a significant difference in the geometric mean diameter of cells before and after compression (P<0.05). Fmax increased with the cell diameter GMD1, but E and Ï?y were independent of the cell geometric parameters as expected. The Fmax, E and Ï?y of single cells in the mesocarp were 2.5±0.6 mN, 0.8±0.2 MPa and 0.03±0.01 MPa respectively. These cell mechanical parameters are intended to be used to model the relationship between macro-scale and micro-scale mechanics of tomato fruits.
Zhiguo Li has completed his PhD at the age of 27 years from Jiangsu University and is carrying out postdoctoral studies of Marie Curie Research Fellow from School of Chemical Engineering, University of Birmingham. His research interest focuses on the evaluation and prevention of mechanical handling damage of fruits and vegetables. He has published 30 papers in reputed journals and has been serving as six journals of editorial board member of repute. He was always invited to be reviewer of 16 international journals in food engineering.
Email: lizhiguo0821@163.com