Measurement of colorimetric parameters in fruits using smartphones and comparison with a tristimulus colorimeter

Resumen

Objectives: Measure color using smartphones on fruits and compare it with the measurement of a tristimulus instrumental colorimeter. Methodology: Fruits at different ripening stages were selected, and colour was measured in a three-dimensional CIEL*a*b* space for strawberries, lemons, tangerines, and chilli peppers. The colorimetric coordinates L*, a* and b* are compared by the color difference of (ΔE*). Seven colourimetric parameters were calculated using colour coordinates to compare the two measurement methods, and the statistical techniques of correlation and Bland-Altman Plot were used to evaluate their performance. Results: The colorimetric coordinates of both methods showed ΔE* values between 2.42 and 59.24 with a greater difference in mandarin fruits and less in peppers, while five colorimetric parameters showed a high correlation coefficient (r=0.943-0.999) for all the fruits evaluated. The Bland-Altman plots showed in detail that the whiteness and yellowness indices did not show similarity, lemon showed a high concordance in five colorimetric parameters, mandarin and strawberry had low similarity and are dependent on their ripening stage. Conclusion: the use of smartphones in the measurement of color in fruits may vary compared to a colorimeter, but their reliability is surpassed when calculating colorimetric parameters that relate the colorimetric coordinates L*, a* and b*, we suggest using these devices as a potential tool to evaluate and monitor the ripening stages of various fruits.