Innovative Technologies and Shelf-Life Extension of Citrus Fruit

Citrus fruit is an important fruit tree crop in the world widely grown in the Mediterranean basin. The harvested fruits are highly appreciated for fresh consumption and, in addition to their flavor, for their positive health values, representing a rich source of bioactive substances that include vitamin C and phenolic compounds such as hydroxycinnamic acids and flavonoids. To preserve postharvest quality of citrus fruit, current strategies to control postharvest decay rely primarily on the application of synthetic chemical fungicides. The combination of legislative restrictions regarding their use, and the increasing consumer demand for a product free of pesticide residues has driven research to find safer and environmentally friendly strategies. In addition, in recent years, interest in citrus marketing has focused on distant besides local markets, raising the demand for appropriate postharvest technologies useful for prolonging fruit shelf-life and obtaining high value-added products. This chapter will discuss the main causes of postharvest citrus quality deterioration, evaluating current knowledge on citrus physiology and pathology. In addition, the safest sustainable strategies for human health will be analyzed with reference to (i) physical methods such as heat treatments, photosensitization, irradiation, LED blue light, and pulsed light technology; (ii) chemical methods including treatments with GRAS compounds, natural antifungal compounds, sanitizers, and reduced-risk fungicides; (iii) microbial biological control; (iv) integrated management; and (v) application of edible coatings. In the last section, advanced postharvest-handling and storage technologies will be presented, including modified atmosphere, packaging, nondestructive methods, and cold treatment, used to preserve the quality of freshly harvested citrus fruit and to extend its shelf-life.