The same raw material was treated by alkali (NaOH 1.25 M
after 4 h incubation at 80 ◦C) [8]; this treatment gives chitin 2
(Table 4). In Table 4, the characteristics of the raw material, chitin
prepared by enzymatic treatment (chitin 1) and that obtained by
alkaline treatment (chitin 2) are compared. The ground shrimp
waste before pre-treatment contained a relatively high contents
of chitin (33.5
±
2.3%) and ash (33.2
±
0.2%). These results are
comparable with those reported by previous studies