Fluorescence method is recommended for predicting carotenoid content in tomato

Many nondestructive techniques have been developed and used for the prediction of phytochemical content in fruit. Colorimeters are usually used to predict carotenoid content in tomato fruit.? The objective of this study was to explore the accuracy of the fluorescence indices as a predictor of carotenoid content in tomato fruit compared to the accuracy of the color indices. Several fluorescence indices were highly correlated with the color indices. Especially, FRF_B, FRF_G, FRF_R, BGF_B, BGF_G, and ANTH_RG were highly correlated with a* and a*/b* with a correlation R between 0.914 and 0.965 (R2 between 0.83 and 0.93). FRF_B, FRF_G, BGF_B and BGF_G were highly correlated with lycopene (R2 between 0.31 and 0.43) and with ?-carotene (R2 between 0.20 and 0.27). These correlations were as high as the correlations between the carotenoids and key color indices such as a* and a*/b* values (R2 between 0.37 and 0.39 for lycopene and between 0.24 and 0.27 for ?-carotene). When lycopene and ?-carotene were predicted using principal component analysis, six fluorescence indices (BGF_R, BGF_G, BGF_B, FRF_R, FRF_G, and FRF_B) showed similar predictive performance when compared to color indices based on cross-validation. A potential shortcoming of a colorimetric method can be found when a sample surface has non-homogeneous colors because it measures only a small area, and this fluorescence method can overcome the shortcoming due to a larger measurement area. Therefore, from practical perspectives, the use of fluorescence indices can be a more effective nondestructive method without a loss of predictive power for the carotenoid content of tomato fruit when compared to the traditional use of color indices. SourcesPrediction of carotenoid content in tomato fruit using a fluorescence screening methodDong Sub Kim, Da Uhm Lee, Jeong Hee Choi, Steven Kim & Jeong Ho LimPostharvest Biology and Technology,?Volume 156, October 2019, 110917https://doi.org/10.1016/j.postharvbio.2019.05.018https://www.sciencedirect.com/science/article/abs/pii/S0925521418308469 Picture by http://fluorescentes.net/, Fluorescencia: C?mo funciona