A Mechanical–Acoustic Technique as a Novel Approach for Table Olive Texture Evaluation

This study investigates the texture of table olives by integrating mechanical, acoustic, and sensory approaches, with particular emphasis on the role of acoustic emission in the perception of crunchiness, a key quality attribute influencing consumer acceptance. Three Italian cultivars (Itrana Bianca, Nocellara del Belice, and Bella di Cerignola), processed using different debittering methods, were analyzed using needle and tip compression tests combined with simultaneous sound recording, as well as Texture Profile Analysis (TPA) and Kramer shear press, alongside sensory evaluation by a trained panel. Needle compression primarily characterized peel properties, identifying Itrana Bianca as having the firmest skin, while tip and Kramer tests, reflecting both peel and pulp, indicated that Bella di Cerignola was the hardest and most consistent sample. TPA revealed that Itrana Bianca exhibited higher elasticity and cohesiveness, whereas Bella di Cerignola showed greater firmness and chewiness. Nocellara del Belice consistently displayed the softest texture. Acoustic measurements suggested that sound emission was mainly associated with peel rupture rather than pulp characteristics and showed limited correlation with sensory crunchiness. Overall, the combined mechanical–acoustic approach provides a more comprehensive evaluation of olive texture and highlights the need for refined sensory descriptors, particularly for peel-related attributes, to better interpret acoustic responses.