Pengaruh Penambahan Kitosan Terhadap Karakteristik Bioplastik Dari Pati Talas (Colocasia esculenta) Menggunakan Plasticizer Sorbitol

Abstract

Bioplastics are plastics based on biological or often referred to a plastic made from renewable resources and can be recycled by biological processes. Starch from the tubers of taro (Colocasia esculenta) is used as a raw material for the bioplastic using sorbitol as plastizicer and chitosan as a filler. This study aims to determine the characteristics and profile of taro starch gelatinization, determine the effect of chitosan and sorbitol to the properties of tensile strength, elongation at break, water absorption and gelatinization profile bioplastics from taro starch. This study uses a casting method in the manufacture of bioplastics with gelatinization temperature 75 oC and a variety starch concentration of 20 % w/v, 30% w/v and 40% w/v. Furthermore, the variation of the addition of sorbitol (10 % w/w, 20 % w/w, 30 % w/w, 40 % w/w and 50 % w/w), and the variation of addition of chitosan (0.5 w/v ; 1 w/v, 1.5 w/v; 2 w/v; and 2.5 w/v). The results showed that taro starch with a particle size of 100 mesh have 93.55 % starch content, 6.5 % moisture content, 0.76 % ash content, 17.9 % amylose, 75.66 % amylopectin, 1.02 % protein, and 1.44% fat. Analysis of the nature of the pasta with the method of Rapid Visco Analyzer (RVA) showed starch taro has a temperature of gelatinization 72.94 °C with peak viscosity 6632 cP, while the taro starch bioplastics have temperature of gelatinization 77.72 °C with a peak viscosity 3476 cP. From the analysis of FT-IR obtained a change of functional groups of O-H of bioplastics at wave number 3765 cm-1 , from the analysis of the morphology of fracture bioplastics obtained that the spread of filler chitosan is uneven and there are still some factions empty. Addition of chitosan and sorbitol affect the properties of tensile strength and elongation at break of bioplastics produced. By increasing variation chitosan increased the value of tensile strength, by increasing variation of sorbitol, the value of the elongation at break increases. The best bioplastics produced on this research is on the composition of starch 40 % w/v with chitosan 2.5 w/v, and sorbitol 30 % w/w which has a value of 8.36 MPa tensile strength and elongation at break value of 22.06%.