Abstract:

This research aimed to study the changes in main nutritional components during the crisping process of grass carp
(Ctenopharyngodon idellus, which was cultured under specific conditions to obtain crisp grass carp). Samples were acquired
periodically and the differences in muscle collagen content, mineral contents and fatty acid composition during the entire
crisping process were compared. Muscles in different crisping periods were taken for determination of mineral elements
by graphite furnace atomic absorption spectroscopy (GFAAS) and fatty acid composition by gas chromatography-mass
spectrometry (GC-MS). The results showed that the collagen content of grass carp was 1.02 g/100 g, which was significantly
lower than that of crisp grass carp (C. idellus C. et V). Compared with those in grass carp, the contents of Ca and Mg in crisp
grass carp were increased by 269.43% and 46.05%, respectively, while the contents of Fe and Cu in crisp grass carp were
decreased by 85.59% and 23.08%, respectively. However, there were no significant differences in the contents of Zn, Cr and
Cd among all the samples examined (P > 0.05). A total of 17 kinds of fatty acids in the muscles collected in different crisping
periods were detected. The ratios of ΣPUFA to ΣSFA ranged from 0.74 to 1.46 and showed the highest value in grass carp.
Meanwhile, the ratios of ΣPUFA and Σ(EPA + DHA) were decreased. The present study indicated that the contents of
muscle collagen, and Ca and Mg were significantly increased while the contents of Fe and Cu and the total amount of PUFAs
were decreased during the crisping process of grass carp.

Key words: crisp grass carp, collagen, mineral content, fatty acid composition, grass carp