Innovative tools to improve storage life of kiwifruit

Kiwifruit is a globally important fruit crop whose economic significance and scientific interest have grown rapidly due to its remarkable nutritional profile and high market value. However, postharvest management remains one critical aspect of the supply chain, as the product’s quality is strongly influenced by storage. The work investigates different innovative technologies aimed at improving the storage life and postharvest performance A. chinensis var. chinensis fruits. The experimental core investigates both technological and biological strategies. Non-destructive vis-NIR spectroscopy, implemented through the KiwiMeter®, was evaluated as a high-throughput tool for in-field and postharvest monitoring of kiwifruit maturity and quality. The results demonstrated strong correlations between IAD indices and key quality parameters, highlighting the potential of the device for precision harvest management. Microbiome-based studies are also presented, firstly characterizing the cultivable epiphytic communities associated with the kiwifruit core microbiome during postharvest cold storage. As direct consequence, it led to the isolation and functional characterization of 119 microbial strains (85 bacteria and 34 fungi), exhibiting various metabolic features and profiles, including the production of plant-beneficial compounds. This functionally rich microbial collection provides a valuable resource to investigate the role of bacterial ACC deaminase, potentially exploitable as ethylene biosynthesis antagonist. Several strains, including L. plantarum and other ACC-deaminase-producing bacteria, were further investigated for their ability to modulate fruits ripening and preserve quality during postharvest storage. The application of these bacteria delayed ethylene synthesis and fruit softening, supporting future studies aimed at developing sustainable, microbially based strategies for postharvest quality preservation. In addition, the thesis examined novel physical treatments such as sound-wave exposure and postharvest LED-light irradiation as non-chemical approaches to influence fruit physiology and quality profile. Both these treatment strategies showed limited, but still promising results in delaying ripening, modulating fruit sugar metabolism, and maintaining quality parameters during cold storage.