Novel food colorants from tomatoes: Stability of carotenoid-containing chromoplasts under different storage conditions
Author(s)
Date Issued
2021
Type
article
Volume
140
Start Page
110725
Abstract
Despite years of research, the application of natural pigments as food ingredients is still limited by their low stability. This research investigated the storability of carotenoid-containing chromoplasts, as novel natural food colorant from unsold tomatoes. The 30-day stability of chromoplasts (Chr), in comparison to free carotenoid-based extract (Free car), was investigated by the kinetic degradation model of carotenoids (UV–visible spectrophotometer assay), and by the color attributes as CIELab* parameters [i.e. total color difference (ΔE); red-yellow ratio (a*/b*) and chroma value (C*)], under dark and UV-light exposure at different temperatures (4, 25 and 40 °C). Regardless of the different storage conditions (temperature and UV-light exposure), the lowest pigment degradation rates were found for Chr [0.014 days−1 (25 °C in the dark) - 0.057 days−1 (40 °C under UV-light)] rather than Free car [0.018 days−1 (25 °C in the dark) - 0.071 days−1 (40 °C under UV-light)]. Furthermore, Chr better retained the colorimetric parameters, especially at 4 °C (ΔE ~ 4.0) and 25 °C (ΔE ~ 4.5) in the dark. These results proving that a tailored enzymatic-assisted extraction allowed the recovery of stable natural red-orange pigments better preserved by their chromoplast envelop.