Maturity is the most important indicator for assessing the quality of tomato fruits. The main criteria for assessing the maturity of tomatoes include color, hardness, size, shape and humidity. In recent years, various fast and reliable non-destructive testing methods have been developed, as well as various multi-dimensional algorithms to measure the quality parameters of different samples during the harvest. The book provides an overview of well-known methods (spectral, hyperspectral, fluorescent, laser, technical vision) of non-destructive testing used to assess the maturity of tomatoes. The effectiveness of these methods has been compared and the best of them have been selected to assess the level of fruit maturity. The fluorescent method presented in this review has great potential to replace traditional procedures because traditional approaches do not allow for quick and effective research on the maturation and maturity of the fruit, such as the internal quality parameter. The proposed technology to measure the ripeness of tomatoes using the fluorescent method is less time consuming and more accurate than the color-dependent methods to determine the ripeness of tomatoes and to separate tomatoes from any color of ripe fruit.