Non-destructive impulse response technique was tested on two melon varieties
(‘Zard-Eyvanekey’ and ‘Sousky-Sabz’) in fi ve diff erent stages of ripening. Resonance
frequency and sound pressure level (SPL) from the impulse response were compared
with mass, elastic modulus, soluble solids contents (TSS) and sensory evaluation.
Among acoustic and destructive parameters, resonance frequency is an indicator
to distinguish of diff erent maturity stage of the melon in both varieties. Th e sound
pressure level (SPL) was not a reliable parameter to evaluate melon ripeness. It was
established that the impulse response technique is useful to decide fruit maturity
stage and appropriate harvest time.