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Minimal processing of fruit and vegetables involves different operations that increase the perishability of the final product and often cause a decrease in its nutritional properties. In this work three blackberry (Rubus fruticosus L.) cultivars (‘Chester’, ‘Arapaho’ and ‘Triple Crown’) grown in the hill (Valle Imagna, BG, Italy) or in the plain (Arcagna, LO, Italy) were evaluated immediately after minimal processing and after 3, 6 and 8 days of shelf-life at 3°C. Following parameters were evaluated: firmness, soluble solids content (SSC), acidity (AC), color (a*, b*, Hue), total anthocyanin (TA), total polyphenols (TP) and antioxidant activity (DPPH). All the cultivars, especially if grown in the plain, showed a slight decrease in firmness during shelf-life, however, they maintained adequate firmness values until the end of the storage. Blackberries grown in the plain had higher SSC and hue and lower acidity than those coming from the hill. ‘Chester’ was the richest in TP and in TA followed by ‘Arapaho’ and ‘Triple Crown’. TA content was always higher in fruits cultivated in the plain compared to those from the hill. Minimal processing did not importantly affect TA, TP content and DPPH. The nutritional content of the fruit at the end of shelf-life was not statistically different from the harvest. All the evaluated cultivars showed good physico-chemical parameters and nutritional properties throughout the storage and, then, they have an interesting potential as ready-to-eat product.

Berry fruits such as blackberry (Rubus fruticosus, L.) and raspberry (Rubus idaeus, L.) are widely consumed because of tradition and taste and for their positive nutritional properties. Their composition is characterized by a low calory and fat content as compared to other types of foods. Moreover, they are characterized by a high content in nutraceutical compounds, such as polyphenols and anthocyanins, that are found active for their protective effect against an excess production of free radicals, due to their antioxidant capacity. Fruit quality firstly depends on the genotypic difference, and secondly on the non-genetic, environmental factors, such as crop location and year of production. This work aims at contributing to the knowledge of the factors influencing Rubus fruit quality, by the comparative analysis of different cultivars of blackberry and raspberry picked during the period 2006-2009 in four locations of Northern Italy with very different pedological and climatic features. A first part of the work is focused on some bio-morphological variables (fruit weight, dimensions, soluble solids and acid content and skin colour measurement. A second part regarded the nutraceutical characteristics of fruit (total polyphenol, ascorbic acid, anthocyanin content and the 2,2-diphenyl-1-pycrilidrazyl – DPPH – assay). Significant differences were found between the analyzed cultivars and the locations, and the work try to contribute to open a discussion on the possible causes involved in these quality changes.