Pengaruh Pelapisan Kitosan-Nisin terhadap Kualitas Ikan Sidat (Anguilla bicolor bicolor) selama Masa Penyimpanan pada Suhu Rendah

Telah dilakukan penelitian mengenai preparasi dan karakterisasi pelapisan kitosan nisin terhadap kualitas ikan sidat (Anguilla bicolor bicolor) selama penyimpanan pada suhu rendah. Penyimpanan dilakukan selama 8 hari pada suhu 5 ± 2 °C. Nisin sebanyak (0, 2, 4, 6 dan 8 g) ditambahkan ke dalam larutan kitosan 1% (b/v), sehingga diperoleh lima larutan pelapis, yaitu kitosan 1,0% dan kitosan-nisin: 0,2; 0,4; 0,6 dan 0,8% (b/v). Pelapis kitosan-nisin optimal diketahui melalui pengamatan terhadap perubahan fisik daging. Tebal lapisan kitosan-nisin diamati menggunakan analisis SEM. Parameter yang diukur selama penyimpanan adalah nilai pH, nilai jumlah cemaran mikroba dengan metode Total Plate Count (TPC), kadar air, kadar lemak dan kadar protein. Hasil penelitian menunjukkan bahwa berdasarkan perubahan fisik selama penyimpanan, konsentrasi kitosan-nisin sebesar 0,6% (b/v) merupakan konsentrasi optimal untuk mempertahankan kualitas ikan sidat. Tebal lapisan kitosan-nissin adalah (0,529 − 0,554) mm. Ikan sidat terlapis kitosan-nisin mengalami penurunan kadar proksimat (air, lemak dan protein), peningkatan nilai pH dan jumlah cemaran mikroba yang lebih rendah dibandingkan ikan tanpa pelapisan. Hal tersebut menunjukkan bahwa pelapisan kitosan-nisin pada ikan sidat dapat mempertahankan kualitas ikan sidat selama penyimpanan pada suhu rendah.Effect of Chitosan-Nisin Coating on Quality of Eel (Anguilla bicolor bicolor) during the Storage Period at Low Temperature. The research of the preparation and characterization of chitosan-nisin as a coating layer on the eel (Anguilla bicolor bicolor) were studied. The quality of the eels after coating was observed during storage at low temperatures. The storage was carried out for 8 days at a temperature of 5 ± 2 °C. A various mass of nisin as much as (0, 2, 4, 6 dan 8 g) was added to 1% (b/v) chitosan solution, thus five coating solutions were obtained, namely 1.0% chitosan and chitosan-nissin 0,2; 0,4; 0,6 and 0,8% (w/v), respectively. The optimalization of chitosan-nisin coating was known through the observation of the physical changes of meat. The thickness of chitosan-nisin layer was observed using scanning electron microscopy (SEM) analysis. The parameters measured during storage are pH value, the amount of microbial contamination using the total plate count (TPC) method, water content, fat content and protein content. The results showed that based on the physical changes during storage, the concentration of chitosan-nisin of 0.6% (w/v) was the optimal concentration to maintain the quality of eel. The thickness of the chitosan-nissin layer was observed of 0.529 – 0.554 mm. Chitosan-nisin coated eel decreased proximate levels (water, fat and protein), increased pH value and lower amount of microbial contamination compared to fish without coating. These phenomena show that the chitosan-nisin coating can maintain the quality of eel during storage at low temperatures.