Fabio Lovati

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.

Mango fruit is a rich source of bioactive compounds such as carotenoids, phenolics, and ascorbic acid. This research aimed at predicting the content of these bioactive compounds in ‘Tommy Atkins’ mangoes using optical properties, i.e., the absorption coefficients related to chlorophylls (µ_a630, µ_a650, µ_a670, µ_a690) and carotenoids (µ_a540), and the scattering parameters (Mie’s A and b), measured during the shelf-life period at 20 °C by time-resolved reflectance spectroscopy. The µ_a540 and Mie’s b increased during shelf-life, while µ_a670 and Mie’s A decreased. Ascorbic acid (AA) and the total antioxidant capacity decreased during shelf-life, while the total carotenoids increased, and the total phenols (TPC) did not significantly change. The major constituent of the nonsaponified extracts, (all-E)-β-carotene, increased during the shelf-life period. A similar trend was observed for the total (all-E)-violaxanthin esters, the total (9Z)-violaxanthin esters and the total neoxanthin esters. Carotenoids are responsible for the yellow-orange color of mangoes: (all-E)-β-carotene was mainly related to a* and h° pulp color while the total (all-E)-violaxanthin esters were mainly linked to b*, C*, and the yellowness index. Using multiple regression analysis, good prediction models were achieved for the total carotenoids (R²_adj = 83.1%), the total xanthophylls (R²_adj = 78%), (all-E)-β-carotene (R²_adj = 77%) and the total (all-E)-violaxanthin esters (R²_adj = 74%), while less satisfactory predictions were obtained for AA and TPC.

Time-resolved reflectance spectroscopy (TRS), a nondestructive technique, can help the industry to provide high-quality fruit to encourage pear consumption. The absorption coefficient measured by TRS at 670 nm (μ_a670) represents a maturity index for pear fruit, with less mature pears high μ_a670 and more mature low μ_a670. The aim of this work was to study the quality characteristics, the sensory profiles and the ethylene production of ‘Abate Fetel’ pears sorted at harvest in different TRS maturity classes and stored in different atmospheres. At harvest, 540 pears were measured by TRS for μ_a670, ranked by μ_a670 in three maturity classes (less-LeM, medium-MeM and more-MoM mature) and randomized in nine samples according to 1-MCP treatment (treated, control), storage time (4–6 months) and atmosphere (air-NA; CA: 8–12 kPa O₂, 1 kPa CO₂). Fruits were examined at harvest and after 7 days of poststorage shelf life for skin color, firmness, soluble solids, acidity and ethylene production and were submitted to sensory analysis. At harvest and after storage, MoM pears were less green and showed a higher SSC content than LeM ones. After storage, MoM pears produced less ethylene and were perceived to be firmer (especially in 1-MCP-treated pears), more astringent and less juicy (when stored for 6 months) than LeM ones.