Nutri Red carrots - how freezing affects carotenoid content

Nutri Red carrots are a variety of red carrots that, in addition to ß-carotene, are rich in lycopene, and could thus be an interesting alternative to tomatoes as a source of lycopene in the European diet.

However, the way carotenoid content changes during processing, especially in the case of freezing, has yet to be fully assessed.

Researchers from the Max Rubner-Institut (MRI) in Karlsruhe (Germany) analysed potential carotenoid degradation following blanching and freezing operations and during storage at low temperatures.

Carrots were sliced, blanched, frozen with an air blast and stored at -50°C, -30°C, -18°C and -15°C for up to two years.

Tests showed that, while β-carotene, α-carotene and lutein content remained stable during processing and long-term frozen storage, trans-lycopene content degraded at all storage temperatures. Nonetheless, despite the significant loss of trans-lycopene, carrot slices still had a lycopene content similar to that of some tomato varieties after one year of storage at -18°C.

This study has therefore shown that the Nutri Red carrot variety is an excellent alternative source of lycopene.

Source: Behsnilian Diana, Mayer-Miebach Esther, 'Impact of blanching, freezing and frozen storage on the carotenoid profile of carrot slices (Daucus carota L. cv. Nutri Red)', 2017, Food Control, Vol. 73, Part B, pag. 761-767.