Variation in the carotenoid composition during storage and cooking in carrots

Carrots (Daucus carota L.) are consumed as an important dietary source of β-carotene (provitamin A), α-carotene and lutein [1]. An HPLC method was applied to determine the content of the carotenoid composition in carrots during storage and cooking [2].

Analyses were carried out at the beginning, 1^st, 2^nd and 4^th weeks, and 2^nd, 4^th months after harvest [3]. In the course of the storage, the carotenoid levels usually decreased, and the decrease was found to be greater at the storage time, 2^nd and 4^th months. Meanwhile, the amount of the carotenoids in carrots leaves was not changed within 2 weeks at 4 after harvest. Moreover, the level of lutein, the main component in carrot leaves, increased from 233.8±11.7 to 346.2±26.7µg/g DW during the first 2 weeks.

The Change in carotenoid contents was observed during home-processing of one Korean cultivar. The carrots fried in oil showed the highest amount of β-carotene (164.3±6.6µg/g DW) and α-carotene (50.1±0.4µg/g DW). Sautéing, pressure-cooking in water and microwaving ranked the second group. The loss of the carotenoids was occurred the most through these cooking processes: boiling in water containing 1% NaCl, braising and baking. The content of lutein increased slightly after boiling in water containing 1% NaCl (9.3±0.4µg/g DW) compared with the control (7.5±0.4µg/g DW), while the loss occurred after the other home-processings.

Acknowldgements: This work was supported by a grant (Code 20070301034017) from BioGreen 21 Program, Rural Development Administration, Republic of Korea.

References: 1. Jayaraj, J. et al. (2007) Transgenic Res. Epub ahead of print. 2. Melendez-Martinez, A.J. et al. (2007) Food Chem. 104:169–175. 3. Cinar, I. (2004) Lebensm.-Wiss. u.-Technol. 37:363–367.