PENGAMBILAN PROTEIN DARI LIMBAH IKAN INDUSTRI PEMPEK DENGAN EKSTRAKSI MENGGUNAKAN ASAM ASETAT DAN PENENTUAN KOMPOSISI ASAM AMINO PROTEIN HASIL

saifrudin, S.Pd, Dr. Chairil Anwar

2011 | Tesis | S2 Ilmu Kimia

Telah dilakukan penelitian pengambilan protein dari limbah ikan industri pempek. Tujuan penelitian ini adalah untuk mengetahui komposisi gizi, jenis dan komposisi asam lemak, mengambil protein dari serbuk limbah ikan dan menentukan komposisi asam amino protein hasil. Penelitian dimulai dengan penyiapan sampel serbuk limbah ikan melalui pencicangan, pengeringan, penggilingan dan penyaringan 100-200 mesh. Lemak pada serbuk limbah ikan diambil melalui metode soxhlet menggunakan petroleum eter (40-60 o C) dan komposisi asam lemaknya ditentukan dengan kromatografi gasspektrometer massa (KG-SM). Protein dalam sampel bebas lemak diekstraksi menggunakan asam asetat glasial dan pengendapan protein pada pH 7. Protein hasil dikeringkan dengan pengering beku dan ditentukan komposisi asam amino dengan menggunakan kromatografi cair kinerja tinggi (KCKT) dan kromatografi lapis tipis (KLT). Hasil penelitian menunjukkan serbuk limbah ikan mempunyai kadar air (7,73%), kadar abu (12,53%), kadar lemak (37,96%), kadar protein (37,06%) dan kadar karbohidrat (4,72%). Komposisi asam lemak pada lemak limbah ikan terdiri atas palmitat (35,31%), stearat (13,56%), miristat (7,48%), oleat (13,53%), palmitoleat (9,15%), vacenat (4,08%), linoleat (1,17%) dan eikosadienoat (1,70%). Pengambilan protein berupa serbuk protein sebesar 19,98%. Komposisi asam amino protein hasil terdiri atas glisin (21,91%), asam glutamat (11,93%), arginin (9,66%), alanin (8,21%), lisin (7,64%), asam aspartat (6,67%), isoleusin (5,41%), leusin (4,12%), valin (2,85%), serin (2,33%), penilalanin (2,11%), metionin (1,30%), tirosin (1,18%) dan histidin (0,87%). Dengan KLT dapat diidentifikasi asam amino lain yaitu asparagin dan prolin. Kandungan asam amino esensial dalam protein hasil mencapai 34% dan skor kimia asam amino esensial secara umum di atas standar FAO/WHO dan NRC Washington. Protein hasil tersebut dapat dimanfaatkan sebagai bahan fortifikasi pangan.

A research on protein recovery from fish waste of pempek industry has been conducted. The purposes of this study were to determine the nutrient composition, type and composition of fatty acid, to recover protein and to determine the amino acids composition found in fish waste. The study was started by preparing some samples, through cutting, drying, milling and screening 100-200 mesh. Fat content in powder of fish waste was taken by soxhlet using petroleum ether (40-60 o C) and fatty acid composition was determined by GC-MS. Protein of fat-free sample was extracted using glacial acetic acid and protein precipitation at pH 7. Then the resulted protein was dried by freeze drying and its amino acids composition was determined by using HPLC and TLC. The results of the experiment showed the fish waste had a moisture content (7.73%), ash content (12.53%), fat content (37.96%), protein content (37.06%) and carbohydrate content (4.72%). Fatty acid composition in fat of fish waste consisted of palmitic (35.31%), stearic (13.56%), miristic (7.48%), oleic (13.53%), palmitoleic (9.15%), vacenic (4.08%), linoleic (1.17%) and eikosadienoic (1.70%). Protein recovery was 19.98% protein powder. Amino acids composition of resulted protein consisted of glycine (21.91%), glutamic acid (11.93%), arginine (9.66%), alanine (8.21%), lysine (7.64%), aspartic acid (6.67%), isoleucine (5.41%), leucine (4.12%), valine (2.85%), serine (2.33%), phenylalanine (2.11%), methionine (1.30%), tyrosine (1.18%) and histidine (0.87%). Other amino acids, asparagine and proline, were identified by using TLC. The essential amino acids in fish waste of pempek industries was containing 34% and chemical score of essential amino acids was commonly above of standard FAO/WHO and NRC Washington. The resulted protein of fish waste could be used for food fortification materials.

Kata Kunci : limbah ikan, protein, ekstraksi, asam amino