Characterization of mechanical properties of two varieties of sweet potato (Ipomoea batatas Lam.)

In this paper a study of some mechanical properties of two varieties of sweet potato (yellow and red) is presented. This with the aim of obtaining data required in process engineering calculations, and in handling and storage of the product. Different tests were used (penetration, compression and bending), to estimate parameters of maximum penetration stress, stress and strain at fracture and modulus of deformability. The texture analyzer TA.XT plus Stable Micro Systems was used. It is concluded that the red and yellow variety have very similar values of compression stress (0.77 and 0.75 MPa) and that the deformation that must be applied to cause fracture are also very similar (21.5 and 20.5%). With respect to the fracture stress, significant differences between the two varieties were observed.