Pengembangan Edible Film Hidrofobik dari Kulit Kakao dengan Penambahan Kitosan dan Virgin Coconut Oil Menggunakan Aplikasi Ultrasound

Abstract

Efforts to reduce plastic production for food packaging can be made by making hydrophobic edible film from cocoa pods with the addition of chitosan, virgin coconut oil (VCO), and ultrasound treatment to produce good mechanical properties. The research method used Response Surface Methodology (RSM) with box-behnken design in determining the optimum point of chitosan, VCO concentration, and ultrasound contact time. The quadratic polynomial equation and surface plot of chitosan increased the tensile strength and elongation but reduced the solubility of hydrophobic edible film. The addition of VCO decreased the tensile strength and solubility but increased the elongation values of hydrophobic edible film. The ultrasound contact time increased the tensile strength, elongation, solubility of hydrophobic edible film. The interaction of chitosan, VCO concentration, ultrasound contact time has a significant effect in determining the response of tensile strength, elongation, solubility which can improve the mechanical and physical properties of hydrophobic edible film. The optimum sample was obtained from 2.454 g chitosan; 1.4 % VCO; 36.5 min ultrasound contact time. The verification stated that the data were acceptable with JIS. FTIR spectra of pectin and chitosan sample produced functional group absorption, such as O-H, C-H (alkane), N-H (secondary amine), C=N (imine), C-O-C (ether), N-H (aldehyde), C-H (alkyne). FTIR spectra produced new absorption groups when VCO and ultrasound treatment were added, namely in the functional groups O-H (free alcohol), C-O (ester), N-H (acid amide). SEM samples were observed in cross section, the pectin and chitosan samples presented a dark ash colour indicating the presence of water in the film; black indicated holes. In the pectin, chitosan, VCO, the ultrasound treatment samples presented an ash colour indicating that the hydrophilic components and VCO were well emulsified; blackish ash indicated the large droplet size of VCO.