PENGARUH LAMA WAKTU PENGASAPAN TERHADAP KOMPOSISI DHA (Docosahexaenoic Acids) IKAN BANDENG (Chanos-chanos Forsks)

Abstract

Besides contain of high nutrition like : protein, lipid, vitamins and minerals, Milkfish also rich in calcium and phosphor and good flavour of this fish has caused of high consumer preferences in Indonesia. One of the most important nutritin compound founded in Milkfish is the omega-3 fatty acids, which is very important to human health. Because of its capability to avoid the blood circulation deseases. One of the method of preservation that implemented by many fish processors is smoking, but the omega-3 fatty acids containing in the lipid of fish is faced highly risk of occuring the reduction of its composition and even possibility of oxidation process and deterioration. The aim of this study is to obtain the effects of smoking duration on the changes of nutrition value, and the composition of omega-3 fatty acids of Milkfish. Analisysis of the products consists of sensory test, proximate analysis and omega-3 /DHA analyisis based on the Indonesian National Standard. Statistical analysis using SPSS program and ANOVA. This research was taken place in two places i.e : the Laboratory of Fisheries Processing Technology, Faculty of Fisheries and Marine Sciences, Diponegoro University and the Laboratory of Food and Nutrition, Gajah Mada University, Yogyakarta. The results of sensory evaluation of fresh fish shows the rate value of 8.1 means that the quality of fresh fish were still in good condition with the characteristics of bright eye, less fresh of gill , whole flesh and neutral odour. While smoked fish A (3 hours smoking duration) get the average sensory value of 8.59 (a little bit lower) and smoked fish B ( 5 hours smoking duration) get the average value of 8.78. This is caused by smoked fish B show more drak appearanced and therefore it looks more well cooked with glossy golden colour. But generally both products are acceptable by the panellists, proved by a high average • sensory value given by the panelists. According to SNI the lowest average value of smoked fish is 7. Proximate composition of fresh Milkfish seems on the normal as the ordinary fresh fish and the composition is as follows : moisture content 75,03%; protein 20,30%; lipid 0,61% dan ash 1,35%, Smoking process has change the chemical composition of fish. Reduction of moisture content of ± 5% on smoked fish A and 6,92% on smoked fish B has increasing the protein content and lipid content on smoked fish A of 3,65% and 1,18%. While on smoked fish B of 7,2% and 2,92%. This changes are causes by smoking duration, temperature of smoking kiln and the wheather condition. When smoking process was raken place. The composition of ash were also changes steadily. One of the most interesting fenomena that occurred in this study was the changing od DHA composition. The smoked fish A show that the DHA value was 121,19 mg/100g, while smoked fish B was sharply decreased until 16,4 mg/100g. This is means that smoking duration has very significant effect to the composition of DHA. Result of SPSS program shows that the probability < 0,05 so that the hypothesis of Ho which is predicted that all of fatty acids populated were identic was rejected and therefore HI which is predicted that all population of fatty acids were not identic was accepted. In other word it was identify that the two method of smoking was significantly different. ANOVA result shows the excistensy of interaction between smoking duration and the fatty acids composition contain in Milkfish. The longer the duration of smoking the lower the fatty acids composition. This fenomena is also shows that the longer the duration of smoking the higher possibility of the oxidation process occurred and the higher possibility of deterioration of DHA. So, it can be concluded that smoking duration should be not more than 3 hours. Ikan Bandeng selain bergizi tinggi karena mengandung protein, lemak,vitam in dan mineral yang kaya akan kalsium dan fosfor juga rasanya lezat gurih sehingga sangat digemari masyarakat Indonesia. Salah satu komponen yang menonjol dalam nutrisi ikan Bandeng adalah asam lemak omega-3 yang sangat berguna bagi kesehatan manusia, karena dapat mencegah penyakit yang berhubungan dengan peredaran darah. Ikan Bandeng sering diawetkan dengan cara pengasapan, namun asam lemak omega-3 dalam lemak ikan ini beresiko mengalami penurunan komposisi dan bahan kemungkinan dapat mengalami kerusakan atau oksidasi. Tujuan penelitian ini adalah untuk mengetahui sejauhmana lama waktu pengasapan dapat berpengaruh pada perubahan nilai gizi dan komposisi asam lemak omega-3 ikan Bandeng. Analisa produk meliputi uji organoleptik, analisa proksimat dan analisa asam lemak terutama asam lemak omega-3 DHA dengan menggunakan metoda yang berdasarkan pada Standar Nasional Indonesia. Analisa statistik menggunakan program SPSS dan ANOVA. Penelitian dilakukan di 3 tempat yaitu : Laboratorium Teknologi Hasil Perikanan, Fakultas Perikanan dan Ilmu Kelautan Universitas Diponegoro dan Laboratorium Pangan dan Gizi, Universitas Gajah Mada Yogyakarta. Hasil uji organoleptik ikan Bandeng Segar menunjukkan nilai 8,1 yang berarti mutu ikan masih sangat baik dengan kriteria mata cerah, insang kurang cemerlang, daging utuh dan berbau netral. Sedangkan ikan asap A (3 jam pengasapan) mempunyai nilai organoleptik rata-rata 8, 59 sedikit lebih rendah dari ikan asap B ( 5 jam pengasapan) yang mendapatkan nilai rata-rata dari panelis sebesar 8, 78. Hal ini disebabkan karena ikan asap B mempunyai kenampakan lebih matang dan warna coklat keemasan lebih gelap. Namun secara keseluruhan dapat diterima dengan baik oleh panelis, dengan nilai cukup tinggi karena menurut SNI batas penerimaan ikan Bandeng Asap adalah 7. Komposisi proksimat ikan Bandeng Segar nampak berada pada nilai normal yaitu kadar air 75,03%; protein 20,30%; lemak 0,61% dan Abu 1,35%. Proses pengasapan telah merubah komposisi proksimat ikan. Penurunan kadar air sebesar ± 5% pada ikan asap A dan 6,92% pada ikan asap B telah meningkatkan kadar protein, lemak dan pada ikan asap A sebesar 3,65%; 1,18%. Sedangkan pada ikan asap B sebesar 7,2% dan 2,92%. Perubahan komposisi ini antara lain dipengaruhi oleh lama waktu pengasapan, suhu pengasapan dan keadaan angin pada saat dilakukan proses pengasapan. Kadar abu mengalami perubahan komosisi yang tidak jauh berbeda. Satu hal yang paling menonjol ditemukan dalam penelitian ini adalah pada komposisi DHA atau asam lemak omega-3 produk. Pada ikan asap A komposisi DHA dijumpai sebesar 121,19 mg/100g sedangkan ikan asap B sebesar 16,4 mg/100g. Ini berarti bahla lama waktu pengasapan sangat berpengaruh terhadap komposisi DHA. Hasil perhitungan program SPSS menunjukkan bahwa probabilitas < 0,05 sehingga Ho yang menyatakan semua populasi asam lemak identik ditolak dan Hi yang menyatakan populasi tidak identik diterima. Dengan kata lain terdapat perbedaan nyata pada kedua perlakuan. Hasil pengujian ANOVA menunjukkan adanya interaksi anta lama waktu pengasapan dengan berbagai jenis asam lemak yang terdapat pada lemak ikan. Semakin lama waktu pengasapan semakin rendah komposisi asam lemak pada lemak ikan. Kecenderungan ini juga dapat mencerminkan bahwa semakin lama waktu pengasapan kemungkinan terjadinya kerusakan asam lemak DHA semakin tinggi. Oleh karena itu disarankan lama waktu pengasapan ikan sebaiknya tidak lebih dari 3 jam.