Formulation of Edible Coatings from Alfalfa Saponins to Enhance the Postharvest Quality of Tomatoes

Tomatoes are a major crop for global exports and have significant nutritional benefits. However, their lifespan is limited due to various biotic and abiotic factors. This study aimed to formulate an edible coating using crude alfalfa saponins coupled with decaglycerol monolaurate (ML-750) and polyoxyethylene (20) sorbitan monolaurate (Tween 20), to enhance the postharvest quality and shelf life of tomatoes by preventing spoilage. The effectiveness of alfalfa saponins coatings, both alone, and with ML-750 and Tween 20, was evaluated by comparing their impact on color, texture, overall acceptability, and % weight loss at 4°C and 25°C for 7 days. Significant improvements were observed in the quality attributes of tomatoes, including firmness, aroma, color, texture, and overall acceptability. Crude alfalfa saponins in emulsified form with Tween 20 increased the shelf stability of tomatoes more effectively than uncoated and ML-750 combined coatings. The total soluble solids (TSS) and pH also play a crucial role in determining the quality of the fruits. The results indicated no significant changes in the TSS of tomatoes coated with encapsulated saponins. Subsequently, a gradual increase in the pH of the coated tomatoes was observed on days 5 and 7, respectively. The findings of this study revealed that alfalfa saponins coupled with synthetic emulsifiers may be a beneficial strategy for prolonging the shelf life and improving the postharvest quality of tomatoes.