Chitin extraction from black tiger shrimp (Penaeus monodon) waste using organic acids

In chitin extraction from black tiger shrimp shell waste, HCl is the commonly used decalcifying agent. However, it is considered a harsh chemical. An alternate was found by using organic acids. Conditions for deproteinization were: 1M NaOH at 95 degrees C for 6 h and solid-to-solvent ratio of 1:15 (w/v). Demineralization involved treatment with 0.25M HCl at ambient temperature for 30 min with agitation. The optimal solid-to-acid ratio was 1:30 (w/v) and this led to 86.5 +/- 1.2% purification of chitin. With the same conditions, the optimal ratio of mixed acids (0.25 M HCOOH and 0.25 M C6H8O7 at 1:2 (v/v)) was 1:28 (w/v) with chitin purification of 88.1 +/- 1.8%.