I. Chemical Composition of Shrimp Heads
Chemical composition of shrimp heads is shown in
Table 1. The average dry matter of shrimp heads was 22.5
± 1.2%. Shrimp heads contained 4 main components:
chitin, protein, minerals, lipid and small amount of
valuable carotenoids. In which, protein accounts for the
highest amount of 54.4%, minerals of 21.2%, lipid of
11.9% and chitin of 9.3%.
Table 1. Valuable components of shrimp heads
Components Contents (%)*
Chitin (%) 9.3 ± 0.8
Protein (%) 54.4 ± 1.8
Minerals (%) 21.2 ± 1.6
Lipid (%) 11.9 ± 1.4
Carotenoids (mg/kg) 206 ± 14
*
based on dry basis.
The protein content of this shrimp heads is higher
than that of processing waste from shrimp Xiphopenaeus
kroyeri(13). These figures have shown that shrimp heads is
a good source for recovery of chitin to produce chitosan
and lipid-mineral-rich protein.
II. Characterization of Chitosan and Lipid-mineral-rich
Carotenoprotein Extracted from Shrimp Heads
The chitosan and purified chitosan were
characterized and the results are presented in Table 2. The
chitosan shows good quality, the protein and ash content
is less than 1% as required(14). Degree of deacetylation of
shrimp reached 82% and chitosan has high viscosity. The
high viscosity of chitosan due to the light treatment
conditions of enzyme combined with dilute NaOH.