APLIKASI MIKROEMULSI β-KAROTEN UNTUK MENGHAMBAT KERUSAKAN FOTOOKSIDATIF VITAMIN C PADA SARI BUAH JERUK Application of β-Carotene Microemulsion to Inhibit Vitamin C Photodegradation in Orange Juice

Orange juice were known have high ascorbic acid content, but susceptible towards photodegradation during storage and display. The objectives of this research were to determine β–carotene microemulsion inhibitory effect on ascorbic acid photooxidation in orange juice and to examine the effect of β–carotene microemulsion application on the sensory qualities. Results of this research showed that β–carotene microemulsion at β–carotene level of 6 ppm (2 % w/w of the system) efectivelly inhibited photooxidation of ascorbic acid in orange juice under 8 hours illumination of 2000 lux fluorescent light. The β–carotene microemulsion was proved as potential inhibitor of asorbic acid photodegradation in orange juice, and the inhibitory effectiveness found to be higher than that of empty microemulsion and free β–carotene. Application of β–carotene microemulsion on orange juice enhanced the juice color and appearance quality when its added after pasteurization. Keywords: Microemulsion, β-carotene, photooxidation, vitamin C, orange juice ABSTRAK Sari buah jeruk merupakan produk pangan yang kaya vitamin C, tetapi rentan terhadap kerusakan fotooksidasif selama penyimpanan dan display. Penelitian ini bertujuan menentukan kemampuan mikroemulsi β-karoten dalam menghambat kerusakan fotooksidatif vitamin C sari buah jeruk dan pengaruhnya terhadap karakteristik sensorisnya. Hasil penelitian ini memperlihatkan bahwa mikroemulsi β-karoten pada konsentrasi β-karoten 6 ppm (2 % b/b terhadap sari buah jeruk) terbukti efektif menghambat fotooksidasi vitamin C sari buah jeruk yang dipapar cahaya fluoresen 2000 lux selama 8 jam. Mikroemulsi β-karoten terbukti mampu berperan sebagai penghambat kerusakan fotooksidatif vitamin C sari buah jeruk yang potensial, dengan penghambatan yang lebih tinggi dibanding mikroemulsi maupun β-karoten. Aplikasi mikroemulsi β-karoten ke dalam sari buah jeruk meningkatkan kualitas warna dan kenampakan sari buah jika penambahannya dilakukan setelah pasteurisasi. Kata kunci: Mikroemulsi, β-karoten, fotooksidasi, vitamin C, sari buah jeruk