Karakteristik Biofilm Berbahan Pati Sagu (Metroxylon sp.) Modifikasi Ikat Silang Asam Akrilat dan Karagenan

Abstract

Biofilm merupakan lapisan tipis menyerupai plastik yang bahan utamanya dapat tersusun dari biopolimer seperti pati. Sagu (Metroylon sp.) merupakan tanaman yang berpotensial dan menjadi alternatif untuk menghasilkan komponen pati sebagai bahan dasar pembuatan film. Modifikasi pati sagu dilakukan untuk menghasilkan sifat pati yang sesuai ketika diaplikasikan dalam pembuatan film sebagai kemasan pangan. Tujuan penelitian (i) merancang proses modifikasi pati sagu melalui ikat silang dengan asam akrilat sehingga dihasilkan pati termodifikasi yang sesuai untuk karakteristik biofilm dan (ii) menganalisis pengaruh penambahan karagenan terhadap karakteristik fisik dan mekanik biofilm berbasis pati sagu ikat silang yang dihasilkan. Modifikasi ikat silang dilakukan dengan penambahan asam akrilat pada jumlah 0%, 3%, 4% dan 5% (b/b). Formulasi pembuatan biofilm mengkombinasikan konsentrasi pati ikat silang (1,25%; 1%; 0,75%) dan karagenan (1,75%; 2%; 2,25%) (b/v). Peubah yang diamati adalah ketebalan, elongasi, kuat tarik, transparansi dan kadar air film. Hasil analisis ANOVA signifikansi 5% memperlihatkan karakteristik film meliputi ketebalan film 0,159-0,191 mm, kuat tarik 0,219-1,228 MPa, elongasi 37,75-63,25%, transparansi 25,26-38,16% dan kadar air film 5,49-8,53%. Peningkatan konsentrasi pati ikat silang dan penurunan konsentrasi karagenan menyebabkan ketebalan dan transparansi meningkat, tetapi kuat tarik, elongasi dan kadar air film menurun. Penambahan asam akrilat menyebabkan ketebalan dan kadar air meningkat, tetapi kuat tarik, elongasi dan transparansi film menurun.

Biodegradable film (biofilm) is a thin layer resembling a plastic whose main material can be composed of biopolymers such as starch. Sago (Metroxylon sp.) is a plant that has the potency and becomes an alternative to produce starch as the basic material for making biofilm. Modification of sago starch was carried out to produce starch with suitable properties when applied in the manufacturing of films as food packaging. The purpose of this study was (i) to design the modification process of sago starch through cross-linking with acrylic acid and (ii) to analyze the effect of adding carrageenan to the physical and mechanical characteristics of the crosslinked sago starch-based biofilm produced. Crosslinking was carried out by adding acrylic acid in the amount of 0%, 3%, 4% and 5% (w/w). Formulation of biofilm production combined concentrations of crosslinked starch (1,25%; 1%; 0,75%) and carrageenan (1,75%; 2%; 2,25%) (w/v). The parameter observed in this study were thickness, elongation, tensile strength, transparency and moisture content of the film. The results of ANOVA analysis with 5% significance showed that the characteristics of the biofilm are film thickness 0,159-0,191 mm, tensile strength 0,219-1,228 MPa, elongation 37,75- 63,25%, transparency 25,26-38,16% and moisture content of film 5,49-8,53%. The increase in crosslinked starch concentration and decrease in carrageenan concentration were proven to affect the increasing of thickness and transparency, as well as the decreasing of its tensile strength, elongation, and moisture content. Meanwhile, the addition of acrylic acid affected to the increasing of thickness and moisture content, but the tensile strength, elongation and transparancy of the biofilm decreased.