Emulsifikasi Minyak Ikan Tuna (Thunnus sp.) dan Stabilitasnya Selama Penyimpanan pada Suhu Ruang

Abstract

Minyak ikan tuna memiliki karakteristik tidak stabil terhadap oksidasi saat penyimpanan, sehingga untuk meningkatkan nilai tambah dapat dibuat menjadi produk emulsi untuk meningkatkan kestabilannya. Tujuan penelitian ini menghasilkan emulsi minyak ikan tuna (Thunnus sp.) yang stabil selama penyimpanan pada suhu ruang. Minyak ikan tuna kasar dimurnikan dengan bleaching menggunakan magnesol XL 5%. Minyak yang dimurnikan dibuat emulsi dengan formulasi minyak 15b/b yang ditambahkan whey protein 0,1; 0,5; 1 (b/b) dan guar gum 1; 1,5; 2 (b/b). Emulsi disimpan pada suhu ruang selama 18 hari. Kestabilan minyak ikan ditentukan dengan pengukuran nilai viskositas, pH, dan perubahan ukuran droplet emulsi selama penyimpanan. Minyak ikan tuna murni memiliki kadar asam lemak bebas 1,3%, bilangan peroksida 2,25 meq/kg, dan anisidin sebesar 2,51% meq/kg. Asam lemak dominan yang terkandung yaitu asam lemak oleat 17,57%, EPA 12,75%, dan DHA 17,75%. Emulsi minyak ikan tuna terbaik diperoleh pada konsentrasi guar gum 2 b/b dan whey protein 0,1 b/b dengan nilai viskositas 8358 cP, nilai pH 4,39, dan ukuran droplet 5,01 µm. Emulsi minyak ikan tuna terbaik memiliki kestabilan hingga hari ke 18 penyimpanan.

Tuna fish oil has unstable characteristics against oxidation during storage. The value can be improve by transforming it into emulsion products to increase its stability. The aim of this study was to produce emulsion of tuna (Thunnus sp.) oil that stable during room temperature storage. The crude tuna oil was purified by bleaching using Magnesol XL 5%. The emulsion was made by mixing 15 b/b oil with whey protein 0,1; 0,5; 1 (b/b) and guar gum 1; 1,5; 2 (b/b). The emulsion was then stored at room temperature for 18 days. The stability of the oil emulsion was determined by measuring the viscosity, pH, and droplet size. Pure tuna fish oil contained free fatty acid 1,3%, peroxide number of 2,25 meq / kg, and anisidin 2,51 meq/kg. The dominant fatty acids observed were oleic acid 17,57%, EPA 12,75%, and DHA 17,75%. The best tuna fish oil emulsion was obtained at 2 b/b guar gum and 0.1 b/b whey protein which was stable during storage at room temperature with a viscosity value of 8358 cP, a pH value of 4,39, and a droplet size of 5,01 µm. The best tuna fish oil emulsion has stability up to 18 days of storage.