Influence of Ripening Stage and Selenium Biofortification on Cherry Tomato Quality During Cold Storage

Preharvest selenium (Se) biofortification is a promising strategy to enhance both the nutritional value and postharvest performance of vegetables. However, its effects on cherry tomato quality during storage, particularly in relation to ripening stage at harvest, remain poorly understood. This study evaluated the impact of foliar Se application (0.5 mM, as Na2SeO4) on carpometric, compositional, and functional traits of cherry tomatoes harvested at two ripening stages (orange-red and deep red) and stored for 0, 10, and 20 days at 11.0 ± 0.5 °C. The Se application increased fruit Se concentration (∼30-fold) and improved dry matter (+8.1%) and firmness (+8.3%) throughout storage. At the end of storage, all fruits showed reduced firmness (up to −44%) and increased fresh weight loss (up to 8.5%), although Se-biofortified fruits consistently maintained a higher dry matter content. The effects of Se on compositional traits were ripening stage-dependent, as it enhanced glucose (+8.2%), fructose (+10.0%), and total sugars (+9.4%) in fully ripe fruits, while increasing titratable acidity in less mature ones (+8.2%). Moreover, Se reduced total carotenoids in fully ripe fruits (−13.2%) but increased ascorbic acid during storage (+19.4%), irrespective of ripening stage. Overall, Se biofortification effectively enriched cherry tomatoes and modulated their postharvest behavior. However, the contrasting, stage-dependent effects of Se biofortification on the functional compounds of cherry tomatoes emphasize the need to refine the biofortification strategy in order to achieve a more consistent and comprehensive improvement in fruit quality.