Research Results

Mango colour and quality

In GreenCHAINge an innovative “smart chain” is being developed. Overall goal is to improve the intrinsic quality of the product on the shelf. Quality of mangoes can be determined by checking the colour of the flesh.

Mango with yellow - orange coloured flesh

Objective

Measuring the colour of the mango flesh gives an indication of the quality / ripeness of ready to eat mangoes. Objective of this work was to determine the correlation of RTE mangos with “internal colour” and to obtain an objective and reliable method to phenotype internal colour.

Experiment and results

The internal colour of more than 3000 mangoes shipped from Brasil to the Netherlands was measured. These mangoes were shipped in 9 shipments between November 2016 and January 2017. Measurements show that increased internal colour (from class 1 (light yellow) to class 5 (dark yellow/orange) correlates with:

  • Decreased firmness
  • Higher ripening temperature
  • More internal defects/browning

“Objective phenotyping” by automatically analyzing color pictures of standardized images, is reproducible and therefore more reliable compared to “subjective” division in five color classes. In addition, measurement of color pixels allows the use of a continuous scale for quality assessment which is more useful for data analysis.

Mango_correlation colour - ripeness.png

Conclusion

Internal color correlates with the ripening stage of mangos. This can be measured precisely with a camera system. A camera system gives a more reliable estimation of the colour than a human operator: it is reproducible. We conclude that objective phenotyping allows for standardisation of internal colour assessments throughout the whole supply chain, reducing human bias and error.