Monitoring attenuation and the elastic properties of an apple with laser ultrasound

Research paper by Sam Hitchman, Kasper van Wijk; Zoe Davidson

Indexed on: 24 Oct '16Published on: 25 Jul '16Published in: Postharvest Biology and Technology


Publication date: November 2016 Source:Postharvest Biology and Technology, Volume 121 Author(s): Sam Hitchman, Kasper van Wijk, Zoe Davidson The firmness of an apple is a commonly used indicator of quality and maturity during sorting and cold storage. Its dependence on the elastic properties means that vibration resonance tests are favored over other – often destructive – tests. We present a novel non-destructive and non-contacting method using laser-generated and laser-detected elastic waves to infer the elastic modulus and Poisson's ratio of an apple from the velocity of surface and body waves. In addition, we analyze the attenuation of these waves. Although the elastic and anelastic properties all decay with age, attenuation is the most sensitive to changes in ripeness of the apple.