Influence of Cooking, Dehydration, and Freeze-Drying on Nutrient Retention and Antioxidant Capacity in Tomato Cultivars

Abstract

This study explores how different thermal processing methods influence the amount of bioactive compounds in five tomato varieties. The samples were subjected to three processing techniques: cooking, dehydration and freeze-drying, which, although commonly used in the food industry to increase the shelf life of foods, could affect the nutritional content of the products. Throughout the study, physical, physicochemical, and biochemical parameters were analyzed to identify changes in the levels of sugars, phenols, carotenoids, lycopene, and antioxidants—compounds that are essential for health. The results demonstrate that dehydration was the treatment that best preserved the amount of phenolic compounds, while freeze-drying was more effective in maintaining high levels of carotenoids and sugars, proving to be a good option for preserving the antioxidant properties of tomatoes. Cooking (sauce), on the other hand, considerably reduced the amount of these bioactive compounds, indicating the need for other viable techniques to preserve the nutritional value of these fruits. Thus, it is concluded that the choice of the processing method is fundamental to maintain the beneficial properties of tomatoes and that some varieties have proven to be more resistant to such losses. As so, this study contributes to both the food industry and the consumer as it guides processing choices that favor the preservation of essential nutrients in tomato-derived products.