Toward Sustainable Ready-to-Eat Salads: Integrating Substrate Management and Eco-Friendly Packaging in Wild Rocket Production

The demand for ready-to-eat salads made from leafy vegetables such as wild rocket (Diplotaxis tenuifolia L.) continues to increase, driven by consumer preference for convenience foods with high levels of bioactive compounds. However, reducing the environmental impact of wild rocket production requires both organically enriched growing substrates and sustainable alternatives to conventional plastic packaging. This study assessed the effects of three cultivation substrates and three biodegradable packaging materials (polylactic acid (PL), cellulose kraft (CK), and kraft-reinforced polylactic acid (PLK)) on the postharvest performance of wild rocket stored at 4 °C for 7 and 14 days. Plants were grown in coco peat (CP), coco peat supplemented with livestock compost (90:10; CP+LC), and coco peat mixed with mushroom compost (50:50; CP+MC). Yield and key pre- and postharvest quality attributes, including nitrate accumulation, phenolic content, antioxidant capacity, colour, and weight loss, were evaluated. The CP+LC substrate resulted in the highest harvest yield, whereas CP promoted higher phenolic content and antioxidant capacity. Among the packaging materials, PLK provided the most balanced internal atmosphere, effectively reducing dehydration and condensation while preserving superior sensory quality after 14 days of storage. Overall, the combination of organic compost amendments, particularly CP+LC, with PLK bio-based packaging represents a promising and sustainable strategy for maintaining postharvest quality and reduce the environmental footprint of minimally processed wild rocket within short food supply chains.