Mechanical properties and microstructure of potato peels

Abstract

Potato peel, as the outermost tissue of the fruit, playing a role of protection and fresh keeping on the pulp tissue, is crucial for the design of potato harvesting machines. In this study, two types of potato 'Yangyu 4' and 'Helan 14' were selected to conduct friction, tensile and tear tests on their peel. Longitudinal and transverse tensile tests were conducted on the peels of two potato cultivars using an electronic universal testing machine, and tear tests were carried out on peels as well. The static friction coefficient for different materials, stress-strain curves and tear force-deformation curves of the peels were obtained and the tensile strength, elastic modulus, failure strain tear strength of the peels were measured. The results showed that the maximum value of the static friction coefficient against metallic materials was 0:616 AE 0:118 and 0:867 AE 0:104 against rubber materials, respectively. The maximum values of the tensile strength, elastic modulus, fracture strain, tear strength were 1.648 MPa, 0.388 MPa, 4.5%, 0.326 kN·m -1 , respectively. Scanning electron microscopy images show that many compact and regular polygonal similar-grain grid structures distributed onty the epidermis surface and microcrack basically did not exist on the peel. The spherical micro-convex structures arranged closely and linearly at the boundary of the grid structure. Hierarchical structure surface with spherical micro-convex structures was one of the reasons for its outstanding friction coefficient. The bearing capacity of the peel depended on the number and distribution of grid structures on the surface, and the size and shape of the epidermal cells. ARTICLE HISTORY

Development and Identification of Working Parameters for a Lychee Peeling Machine Combining Rollers and a Pressing Belt

“…In order to design a suitable fruit processing machine, it is essential to determine the fruit's mechanical properties. The existing literature reveals numerous investigations to characterize the mechanical properties of fresh fruits, including longan [30], watermelon [31], potato [32], kiwi [33,34], and orange [35]. In terms of lychee fruits, Chen et al [36,37] conducted both compression and tensile tests to determine the elastic modulus, rupture force, failure energy, stiffness, and failure strength of fresh lychee fruits and their stones.…”

Experiment and finite element simulation of friction factor and stack damage between blueberries

“…To measure the friction properties between fruit and different materials, many test methods have been utilized. The inclined plane method is one of the extensively used methods (Ekrami‐Rad et al, 2011; Li et al, 2018; Shi et al, 2022). The disadvantage of an inclined plane is that most spherical fruits roll when they sliding on an inclined surface, which causes larger test errors in the measurements.…”

Frictional collision acceleration and damage of potato peel: an experimental study

“…Researches on the friction characteristics of potato peel were limited to the analysis of friction coefficient between potato and different materials by the slope method. [16][17][18] Based on these studies, there have been studies on the normal collision of potatoes and friction research of various agricultural materials, but there are few studies on the friction of potato, especially on the frictional collision and peel damage of potato colliding with rod. One of the main reasons is the lack of the potato peel frictional collision test device.…”