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A DA-meter, a hand-held instrument developed from Vis/NIR spectroscopy, and a portable chroma meter based on CIELab coordinates were used to classify the maturity stage of six early-to-late apricot varieties at the wholesale market, using the linear discriminant analysis (LDA) and the k Nearest Neighbours (k-NN), and to predict their quality and nutraceutical attributes by a stepwise regression analysis. Results pointed out a significant variation among cultivars analysed, regardless of the ripening season. LDA highlighted the key role of fresh weight and flesh firmness (FF), and to a lesser extent of sugar content (TSS) and dry matter (DM), in discriminating apricot cultivars. Based on LDA results and DA-meter index (IAD), it was possible to distinguish samples into four robust ripening classes (0.00-0.10; 0.11-0.20; 0.21-0.30; >0.30). The colorimetric indices allowed to define three classes (a* 70; a* from 5 to 20; a*>20) and to assess the relative ranges of TSS and DM values. Finally, good predictive multi-cultivar models were carried out for TSS, DM, FF, and total carotenoid content (R2: 0.60–0.65). These techniques are promising tools to assess fruit quality, to identify fruit uniform ripening classes and to predict the quality attributes of early-to-late fresh apricots.

In the present study, eight early-ripening apricot cultivars of the Italian and international germplasm were evaluated during three years of investigation (2013–2015), according to their quality traits, biochemical composition, antiradical capacity and hydroxycinnamic acid (HCA) profile, using a chemometric approach. Among cultivars analysed, the highest fresh weight was detected in ‘Maia’ (106 ± 3 g), whereas the lightest fruits were produced by ‘Ottavianese’ cv (51 ± 4 g). ‘Orange Rubis’ and ‘Maia’ were characterized by the highest levels of dry matter, which represent a key processing parameter for the production of dried apricots. The highest content of bioactive compounds such as total phenols and flavans were found in ‘Spring Blush’, Orange Rubis’ and ‘Monaco Bello’, indicating a greater susceptibility to browning during processing. Chlorogenic acid was the most abundant hydroxycinnamic acid found in all tested genotypes, being ‘Portici’ the richest one (338 ± 21 μg g −1 on dry basis). High significant correlations were found among parameters analysed, especially between colour coordinates and bioactive compounds. Finally, application of stepwise discriminant analysis to apricot samples showed that total phenols, total flavans and antiradical capacity were the most important variables to differentiate the cultivars analysed. Besides, principal component analysis made it possible to establish similarities among the cultivars depending on their quality and biochemical characteristics. It is concluded that the combination of quality, biochemical traits analysis and chemometric techniques can be used as a consistent procedure to provide breeders with useful information about the identification and characterization of the most promising early ripening genotypes, both for fresh consumption and processing.

The use of natural compounds to preserve fruit quality and develop high value functional products deserves attention especially in the growing industry of processing and packaging ready-to-eat fresh-cut fruit. In this work, potential mechanisms underlying the effects of postharvest biofumigation with brassica meal-derived allyl-isothiocyanate on the physiological responses and quality of ‘Hayward’ kiwifruits were studied. Fruits were treated with 0.15 mg L−1 of allyl-isothiocyanate vapours for 5 h and then stored in controlled atmosphere (2% O2, 4.5% CO2) at 0 °C and 95% relative humidity, maintaining an ethylene concentration