Evolution of quality attributes in pomegranate peel and arils during fruit maturation

The fruit exterior colour plays a significant role in influencing the consumer preference as well as their acceptance or willingness to purchase the produce. Therefore, the colour of pomegranates directly affects the marketability of the fruit and its products e.g., juice. Currently, little has been researched about the relationship between the external and internal colour changes of pomegranate at different harvest stages. This study aimed to determine the interaction between the fruit part, harvest stage and the five factors contributing to colour, namely: lightness (L∗), chroma (C∗), hue angle (h°), red colour (a∗), yellowness (b∗) and yellowness index (YI). Pomegranate 'Wonderful' fruit was collected from Blyderverwacht farm in the Western Cape, South Africa at two different maturity stages, 153 and 160 d after full boom. The results showed that there was no significant link between the red colour of the peel and arils at all harvest stages. Generally, fruit peel was characterised by higher red colour than the arils at all harvest stages. There was a strong correlation (r²=0.97) between chroma (C∗) and red colour (a∗) for arils of fruit at harvested at 153 and 160 d after full bloom (DAFB). High lightness (L∗) was observed in albedo compared to the peels and arils across all harvest stages. In addition, principal component analysis plot revealed that fruit peel is strongly associated with high red colour and chroma (C∗) at all harvest stages. The study showed that there was no link between the development of external and internal colour qualities, which also confirmed the lack of colour attributes correlation between fruit fractions.