2.2. Extraction of carotenoids
Cephalothorax, cuticles, pleopods, and tails from shrimp (L.
vannamei) were homogenized to a particle size ofz5 mm. Aliquots
of the homogenate (10 g) were mixed with ethyl acetate (50 mL)
and stirred at room temperature in darkness for 30 min; after
extraction the sample was filtered through Whatman No. 1 filter
paper, and the filtrate was evaporated under vacuum to dryness.
The lipid extract obtained was stored at 30 C in darkness.
Tomatoes bought in a local market were dipped in boiling
water for 2 min and then peeled, and the peels were freezedried.
Afterwards, freeze-dried tomato peels were ground with
a mill (0.05e0.02 mm particle size) and stored in bottles protected
from light at 20 C until extraction. One gram of dried
peel was mixed with ethyl acetate (50 mL) and stirred at room
temperature in darkness for 15 min. After extraction the sample
was filtered through Whatman No. 1 filter paper; extraction was
performed twice; the solvent was evaporated under vacuum to
dryness and the lipid extract obtained was stored at 30 C in
darkness.
Commercial b-