Citation
Diezma Iglesias, Belen and Ruiz-Altisent, Margarita and Barreiro Elorza, Pilar
(2004).
Detection of internal quality in seedless watermelon by acoustic impulse response.
"Biosystems Engineering", v. 88
(n. 2);
pp. 221-230.
ISSN 1537-5110.
https://doi.org/10.1016/j.biosystemseng.2004.03.007.
Abstract
Recent commercialisation of seedless watermelon varieties relies on the guarantee of a high quality product. Several internal defects may deteriorate greatly this fruit: (a) creases and/or large voids in the flesh, (b) overripeness and (c) bruises due to impact. The objective of this research was to develop a feasible non-destructive procedure for detecting these defects in individual fruits, based on acoustic impulse response.
A device consisting of a microphone, structural elements and a mechanical impact generator was designed and tested. Good and defective seedless watermelons were tested with the acoustic device. Spectral parameters were examined as potential non-destructive predictors of internal disorders. Waveband magnitude parameters, obtained by summing the magnitude of the spectrum between two frequencies in a specified band width (always including between 40 and 500 Hz), were the acoustic parameters showing the best ability to detect internal disorders.