Elaboration of modified starch-based film from yam variety espino (dioscorearotundata) for use in food packaging

Abstract

The aim of this research was to produce a modified starch-based film of the buckthorn yam variety (diocorearotundata) for use in food packaging. Native starch was first obtained, then the starch was chemically modified and a qualitative and quantitative determination of acetyl groups and substitution grade was made. film formulation was also optimized and the physical and mechanical characteristics of each of the films obtained were evaluated to select the formulation to be used. Finally, it was applied in a sausage type meat sausage. The slice of sausage used for coating with the control and autochthonous film showed greater weight loss compared to slices covered with modified starch. The slice of sausage used for coating with the control and native film showed higher losses compared to the slices covered with modified starch. The film made by modification can be promising for use in meat products. I. INTRODUCTION Limited fossil fuel reserves and the environmental impact caused by the use of non-biodegradable plastic containers have led to the use of biopolymers recognized as safe for human consumption, such as starches, cellulose derivatives, chitosan/chitin, gums or plant-based proteins. These materials offer the possibility of thin films and coatings to cover fresh or processed foods for extended shelf life [1]. Starch is an abundant, economical and naturally renewable polysaccharide, which is widely applied in various areas of polymer science,it has been successfully used in the packaging industry and is readily biodegradable in soil. However, native starch has several disadvantages such as processability and poor solubility in common organic solvents that limit its broad applications. Chemical modifications of starch, including esterification, are effective methods for improving the properties of starch. Acetylated starch is a starch ester that has been studied over the past two decades [2]. Chi et al.,[3] used FTIR to detect the structure of acetylated starches, reporting a substitution degree (SD) of 0.85,1.78 and 2.89. The FTIR spectra of different DS of acetylated starch showed some new absorption bands at 1754,1435 and 1240 cm-1 assigned to carbonyl C=O, CH 3 anti-symmetric deformation vibration and carbonyl CO stretch vibration. These new absorptions suggest that acetylated starch products formed during the esterification process. With the esterification process, acetyl groups were introduced into starch, proton resonances of anhydroglucose unit showed some changes compared to native starch. The modified starch, part of the hydroxyl groups in units of anhydroglucose are converted into acetyl groups. Acetylated 0.01-0.2 starch low (DS) has been applied in many areas, such as film formation, bonding, adhesion, thickening, stabilization and texturing. Acetylated starch with low DS is commonly obtained by esterification of native starch with acetic anhydride in an aqueous medium in the presence of an alkaline catalyst [4]. The inserted acetyl groups cause a reorganization of the starch at a structural lev...