<![CDATA[ABSTRACT The purpose of this study was to determine chemical (water, ash, protein, and lipid contents) as well as fatty acids (saturated fatty acids (SAFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acid (PUFA) composition of juvenile tilapia GIFT at the harvesting period of two, three, and four weeks. This study used a completely randomized design (CRD), consisting of one treatment (harvesting period of two, three, and four weeks) and three repetitions. The data were analyzed using analysis of variance (ANOVA) and the Duncan Multiple Range Test (DMRT) at a 95% confidence level. The harvesting period of two, three, and four weeks had a significant effect (P<0.05) on chemical and fatty acids composition. Lipid contents decreased significantly (P<0.05) at 2-4 weeks harvesting period while water, ash, and protein contents increased significantly (P<0.05). Juvenile tilapias GIFT had total fatty acids of 91.87%, 75.69%, and 62.24% at harvesting periods of two, three, and four weeks, respectively. Total fatty acids decreased significantly (P<0.05) during the two to four weeks harvesting period. Keywords: chemical composition, fatty acid, harvesting period, juvenile tilapia GIFT ABSTRAKTujuan penelitian ini untuk menentukan komposisi kimia (kadar air, kadar abu, kadar protein dan kadar lemak) dan asam lemak (asam lemak jenuh (SAFA), asam lemak tak jenuh tunggal (MUFA) dan asam lemak tak jenuh jamak (PUFA) juvenil ikan nila GIFT pada umur panen 2 minggu, 3 minggu dan 4 minggu. Metode penelitian ini menggunakan rancangan acak lengkap (RAL) yang terdiri dari 1 jenis perlakuan (umur panen yaitu 2 minggu, 3 minggu, 4 minggu) dan 3 kali ulangan. Data di analisis menggunakan Analisys Of Varian (ANOVA) dan uji lanjut Duncan Multiple Range Test (DMRT) pada taraf kepercayaan 95%. Umur panen 2 minggu, 3 minggu dan 4 minggu berpengaruh nyata (P<0.05) terhadap komposisi kimia dan asam lemak. Kadar lemak menurun secara signifikan (P<0.05) pada umur panen 2 minggu, 3 minggu dan 4 minggu. Kadar air, kadar abu dan kadar protein meningkat secara signifikan (P<0.05) pada umur panen 2 minggu, 3 minggu dan 4 minggu. Juvenil ikan nila GIFT mengandung total asam lemak pada umur panen 2 minggu, 3 minggu dan 4 minggu berturut- turut sebesar 91.87%; 75.69% dan 62.24%. Total asam lemak menurun secara signifikan (P<0.05) pada umur panen 2 minggu, 3 minggu dan 4 minggu. Kata Kunci : asam lemak, juvenil nila GIFT, komposisi kimia, umur panen ]]>
