Determination of yield qualitative and hygienic traits in table grapes protected with bags

Table grape represents one of the most important fruit products in southern Italy. In particular, in Sicily the use of cultivars with large ripening period and the adoption of semi-forcing techniques, allows to extend the traditional supplying period both for extra-early and extra-late production. This study aimed to evaluate the influence of grape bunches bagging on morphological, mechanical, chemical and hygienic characteristics of ‘Italia’ berries. To this extent, bunches were bagged with 3 different types of bags (Pergamin, Paper and TnT) at pea size development stage (BBCH 75) and compared with an unbagged bunches (control). At harvest, bunches weight and length, number of berries per cluster, berry lenght and width, berry mass, soluble solids content, titratable acidity, skin colour, and mechanical properties were determined. Bagged bunches, independently from the bag type, were always heavier than non-bagged ones. Berry skin break force was lower in the bunches subjected to bagging, determining a softer and easier-to-chew skin. Bagging also influenced different quality parameters. Overall, bagged bunches always reached the quality level required by the market, confirming the suitability of such a technique for table grape production. Moreover, a significant reduction of agrochemicals (mainly pesticides) residuals in the bugged bunches has been recorded as compared to unbagged ones. The results suggest that bagging practices in table grapes can be a valid strategy to be used for sustainable production to protect the bunches from biotic and abiotic agents reducing the residues of agrochemicals in the product.