Limbah cangkang kepiting bakau hasil budidaya kepiting soka yang menumpuk mengakibatkan pencemaran lingkungan. salah satu cara tepat guna dalam penanganan limbah adalah mengolah cangkang kepiting bakau menjadi kitosan. penelitian terkait modifikasi pada tahap demineralisasi perlu dilakukan karena kepiting bakau mengandung mineral yang sangat tinggi sehingga akan mempengaruhi karakteristik mutu kitosan yang dihasilkan. tujuan penelitian ini adalah mendapatkan karakteristik mutu kitosan dari limbah cangkang kepiting bakau (scylla sp) pada perlakuan tahap demineralisasi yang berbeda melalui analisis rendemen, kadar air, kadar abu, nitrogen total, fourier transform infrared (ftir) dan derajat deasetilasi (dd). metode penelitian ini menggunakan deskriptif kuantitatif. hasil penelitian ini menujukkan nilai rendemen kitosan a(1:10) 29,69% lebih tinggi dari pada kitosan b(1:15) 4.66%. nilai kadar air, abu, nitrogen total kitosan a(0,30%, 1,08%, 1,68%) lebih tinggi dari kitosan b(0,14%, 0,98%, 1,43%), namun keduanya sesuai dengan standar protan laboratory 1987, efsa 2010, dan sni no. 7949-2013. hasil ftir mengkonfirmasi kitosan standar dan kitosan hasil penelitian menunjukkan range serapan yang dekat sehingga tidak terlihat perbedaan signifikan. derajat deasetilasi pada kitosan a(47%) belum memenuhi standar, sedangkan kitosan b(76%) sesuai dengan standar protan laboratory 1987 dan sni no. 7949-2013 (≥76%) namun belum memenuhi standar efsa 2010. perlakuan demineralisasi yang berbeda berpengaruh terhadap karakteristik mutu kitosan cangkang kepiting bakau yang dihasilkan. kata kunci: derajat deasetilasi, ftir, mutu, rendemen

Mangrove crab shell produced by the soft-shell crab’s cultivation that accumulates causes environmental pollution. one of the most effective ways to handle it is to process crab shells into chitosan. research related to modifications at the demineralization stage needs to be done because mangrove crabs possess very high minerals that will affect the chitosan quality produced. the research aim was to gain the quality characteristics of chitosan from scylla-spp shell at different stages of demineralization treatment through analysis of yield, water content, ash content, total nitrogen, fourier transfrom infrared (ftir) and deacetylation degree (dd). this research method uses quantitative description. the result showed that the chitosan yield is a(1:10) 29.69%, higher than chitosan b(1:15) by 4.66%. the value of water content, ash, and total nitrogen chitosan a(0.30%, 1.08%, 1.68%) is higher than chitosan b(0.14%, 0.98%, 1.43%), but both met the standards of protan laboratory 1987, efsa 2010, and sni no. 7949-2013. the ftir result confirmed that standard chitosan showed a close absorption range, indicating no significant difference. however, deacetylation degree analysis showed that only chitosan b met the 1987 protan-laboratory standard and sni no. 7949-2013 with the value of 76%, while chitosan a only achieved 46% below the standard (76%), but both are not achieving 2010 efsa standard. differentiated demineralization treatments will influence the chitosan characteriscs quality of mangrove crab shells. keywords: deasetylation degree, ftir, quality, yield