Formulasi mikroemulsi beta-karoten untuk menghambat kerusakan vitamin C dalam sistem aqueous akibat fotooksidasi

ARIVIANI, Setyaningrum, Prof. Dr. Ir. Sri Raharjo, M.Sc

2009 | Tesis | S2 Ilmu dan Teknologi Pangan

Fotooksidasi dalam sistem pangan menyebabkan hilangnya beberapa zat gizi, terbentuknya off-flavor, warna yang tidak dikehendaki dan toksin sehingga pangan menjadi tidak diterima konsumen. Penelitian ini bertujuan untuk membuat mikroemulsi β-karoten yang stabil dan menentukan efektivitasnya dalam menghambat fotooksidasi vitamin C sistem aqueous. Mikroemulsi dibuat menggunakan kombinasi 3 surfaktan non ionik dengan nilai HLB rendah, sedang dan tinggi. Mikroemulsi yang stabil diisi dengan β-karoten sehingga dihasilkan mikroemulsi β-karoten 300 ppm. Aplikasi mikroemulsi β-karoten dalam sistem aqueous pada konsentrasi β-karoten 6 ppm, setara dengan 2% terhadap sistem. Mikroemulsi β-karoten terbukti efektif menghambat fotooksidasi vitamin C sistem pangan aqueous dengan penghambatan lebih besar dibanding mikroemulsi saja (empty microemulsion) maupun β-karoten langsung (free β-carotene). Aplikasi mikroemulsi β-karoten ke dalam sari buah jeruk meningkatkan kualitas warna dan kenampakan sari buah jeruk tersebut jika penambahannya dilakukan setelah pasteurisasi.

Photooxidation in food system causes nutritional losses and produces undesirable flavor, toxic and color compounds, which make foods unacceptable to consumers. The objective of this research was to obtain stable β–carotene microemulsion and to determine its inhibitory effect on vitamin C photooxidation in aqueous food system. Microemulsion was prepared using combination of three different nonionic surfactants having low, medium and high HLB values. Once a stable microemulsion was obtained, β–carotene was incorporated into the microemulsion at a level of 300 ppm. The β–carotene microemulsion was applied in aqueous food system at β–carotene level of 6 ppm (2% of the system). Photooxidation of vitamin C in aqueous food system was effectively inhibited by β–carotene microemulsion, and its 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.

Kata Kunci : Mikroemulsi,Beta,karoten,Fotooksidasi,Vitamin C,Sistem aqueous, microemulsion, β–carotene , photooxidation, vitamin C, aqueous system