Color‐pigment correlation in virgin olive oil

TLDR

Oil color changes across olive varieties and ripeness stages are directly linked to pigment content and the a* and b* chromatic values. The study aims to evaluate chlorophyll and carotenoid content as an additional quality attribute for virgin olive oil. The authors determined chlorophyll and carotenoid levels in oils from five varieties at different ripeness using chromatic ordinates L*, a*, b* from the absorption spectrum. Statistical analysis shows a strong correlation between pigment content and color parameters, with carotenoid content and b* exhibiting the highest correlation coefficient and being easily measured.

Abstract

The chlorophyll and carotenoid content of virgin olive oils from five varieties harvested at varying degrees of ripeness were determined. Colors were evaluated from the chromatic ordinates L*, a*, b* of the absorption spectrum. Oil color changes for different varieties or stages of ripeness are directly related to pigment content and a* and b* values. The statistical study made on both series of parameters proves that there is a good correlation between them. The carotenoid content and b* have one of the best correlation coefficients (r) and is easily measured. This methodology evaluates chlorophyll and carotenoid content, an additional attribute for evaluation of virgin olive oil quality.