Abstract:

The effect of mechanical processing and oil addition on the bioaccessibility of β-carotene from carrots was
investigated. β-Carotene concentration was determined by high performance liquid chromatography (HPLC) and the
bioaccessibility of β -carotene from three types of processed carrots (1 mm cubes, 8 mm cubes and grated carrot) was
assessed by in vitro digestion model. The fraction of β-carotene transferred from the food matrix to a supernatant and a
micellar phase was also investigated. The highest bioaccessibility of β-carotene measured in the supernatant and the micellar
phase was observed in grated carrots, followed by 1 mm cubes and 8 mm cubes. The bioaccessibility of β-carotene in
both the supernatant and the micellar phase was greatly enhanced after oil addition and highly correlated with oil content.
Although the above-mentioned ranking of bioaccessibility remained unchanged after oil addition, there was a significant
difference in increment rate among three types of mechanical processed carrots. Compared with no oil addition, the addition
of 10% oil could result in approximately 16-fold and 6-fold increases in β-carotene bioaccessibility of the supernatant and
the micellar phase from grated carrots, approximately 6-fold and 4-fold increases for 1 mm cubes, and 12-fold and 2-fold
increases for 8 mm cubes, respectively.

Key words: carrots, β-carotene, mechanical processing, dietary oil, in vitro digestion, bioaccessibility