Alginate-Based Edible Coating to Preserve the Quality and Extend the Shelf Life of Fresh-Cut Salad

The food industry is actively seeking solutions to reduce or replace conventional petroleum-based plastic packaging and, at the same time, to identify strategies that limit the rapid deterioration of fresh products. In this context, the present study evaluated the effectiveness of an edible emulsion coating based on lemongrass essential oil and alginate in delaying the spoilage of Lactuca sativa salad. Following rheological investigation, 1% alginate emulsion was selected as the coating formulation and applied by spraying onto fresh-cut lettuce, and the effect of the treatment was monitored throughout storage. Fresh-cut Lactuca sativa salad was assessed in terms of weight loss, pH, titratable acidity, visual appearance, sensory analysis, and microbiological contamination. Measurements of weight loss, pH, and titratable acidity indicated the lack of significant differences between coated and uncoated salads leaves. However, coated samples exhibited improved quality in the first 8 days of storage, particularly with evidence of a reduction in psychrotrophic and mesophilic bacteria. The proposed coating also helped to preserve the visual appearance of the leaves, with no visible browning during storage, and the sensory evaluation results were encouraging. Overall, these findings suggest that the technology investigated is promising for supporting the use of emulsion-based edible coatings to reduce the rapid spoilage of Lactuca sativa salad during storage.