Evolution of pigments and their relationship with skin color based on ripening in fruits of different Moroccan genotypes of apricots (Prunus armeniaca L.)

- Physical and chemical analysis of the apricot color and their evolution according to genotype and ripening effects.
- CIELAB parameters (a*, b* and C*) are a good indicator for chlorophylls and carotenoids contents evolution. It could be used for prediction of pigments content in apricot fruit.
- Interesting contents of carotenoids and provitamin A in Moroccan apricots represent an asset for the apricot sector development either for fresh consumption or for industrial processing.

Among the characteristics of the quality of apricots, the color of the fruit plays a very important role in the choice of fruit for fresh consumption or in technology of apricots processing.Ten new different apricot clones (Boum A2, Agdez LG1, Marouch 4, Ab5, Marouch 16, RTil 4, Clone C, Mans15, AgdezC2, Cg2) were collected during two different stages of ripening (M1:semi-ripe and M2:ripe). Parameters of apricot fruits color (un-blush and bush) L*, a*, b*, hue angle (H°), Chroma (C*), amounts of chlorophyll a, chlorophyll b, total chlorophylls, β-cryptoxanthin, γ-carotene, β-carotene, Provitamin A, and total Carotenoids were determined. Pigment analysis showed that apricot clones were significantly different (p < 0.05). It was found that the contents of chlorophyll compounds (chl-a and chl-b) in all apricot clones significantly decreased with ripening while carotenoid compounds increased.Among the 10 apricot clones, a correlation was found between color parameters and pigment evolution. The variables a*, b*, and C are correlated positively with the total carotenoids (r > 0.755) and negatively with the chlorophyll content (r < −0520). This relation revealed the importance of these parameters in the development of pigment's color and therefore in monitoring the maturation of apricots. The principal component analysis (PCA) allowed observing that color of examined apricots was found to be dependable on the type of the clone and stage of maturity.However, we found a richness of Moroccan apricots in carotenoids and in Provitamin A, this information will be helpful in the development of the apricot sector either for fresh consumption or industrialization in the region.