The
demineralization conditions used in this study reduce the mineral
content to permissible limits in the chitin. Indeed, the ash content
was reduced to about 1.9%. This was lower than that found by Sini
et al. [32]. This low ash content for chitin indicated the suitability
of removal of calcium carbonate and other minerals from the
raw material. There were no significant differences in the moisture
content and ash among the two chitins (p > 0.05). An important
difference concerns the protein content significantly higher in the
chitin isolated after enzymatic deproteinization (p < 0.05); complete
removal of the residual protein associated with the chitin was
not achieved even if the residual yield is lower than usually found
in literature.