Chromatic analysis for predicting anthocyanin content in fruits and vegetables

Abstract

The objective of this study was to develop simple mathematical models for the prediction of the total anthocyanin content of fruits and vegetables, using colorimetry. Phenolic extracts of 13 species of fruits and vegetables were produced using 70% acidified ethanol and 70% ethanol. The quantification of the total anthocyanins of the extracts was performed by the spectrophotometric method, and the color characterization was done through the tristimulus colorimeter. The correlation between the L* value and the anthocyanin content was high (r =-0.95) for extracts produced with 70% ethanol and diluted 20 times. Linear equations based on colorimetric coordinates, with R2 from 0.80 to 0.99, were obtained using 70% ethanol and 70% acidified ethanol as extraction solvent, with or without dilutions. Therefore, colorimetry, as a rapid method that does not involve the use of specific solvents, can be used to predict the total anthocyanin content of fruits and vegetables.