Optimization of conditions for isolation of high quality chitin from shrimp processing raw byproducts using response surface methodology and its characterization.

Chitin is one of the most abundant bioactive biopolymer
on earth. It is commercially extracted from seafood
processing crustacean shell byproducts by harsh thermochemical
treatments. The extraction conditions, the source and pretreatment
of raw material significantly affect its quality and
bioactivity. In this investigation response surface methodology
(RSM) has been applied to optimize and evaluate the interaction
of variables for extraction of high quality chitin from
shrimp processing raw byproducts. Variables such as, concentration
of HCl (%, v/v) 4.5 (for wet) and 4.9 (for dry), reaction
time 3 h, solid liquid ratio of HCl (w/v) 1:5.5 (for wet) and
1:7.9 (for dry) with two treatments achieved >98 % demineralization
of shrimp byproduct. Variables such as, concentration
of NaOH 3.6 % (w/v), reaction time 2.5 h, temperature 69.0±
1 °C, solid liquid ratio of NaOH 7.4 (w/v) and two treatments
accomplished >98 % deproteinization of demineralized
byproducts. Significant (p≤0.05–0.001) interactive effects
were observed between different variables. Chitin obtained in
these conditions had residual content (%, w/w) of ash <0.4 and
protein <0.8 and the degree of N-acetylation was >93 % with
purity of >98 %. In conclusion, the optimized conditions by
RSM can be applied for large scale preparation of high quality
chitin from raw shrimp byproduct.