Physical and Mechanical Characteristics of Edible Film Based on Lesser Yam Starch with Addition of Glycerol and Sodium Tripolyphosphate

Abstract

Biodegradable food packaging is important to be expanded to reduce the increasing waste in the world. An edible film based on lesser yam (Dioscorea esculenta L. Burkill) has the potential to be innovated and expanded, which contained starch yield up to 21.4 %. Several starch properties obstruct edible film characteristics. It cannot tolerate acid and high temperature, which produces suspension with inconsistently gel-forming, syneresis probability of starch gel is high, limited solubility in water. Therefore, starch modification by crosslinking agent addition should be developed. The purpose of this research was to determine the effect of glycerol (C3H8O3) and Sodium Tripolyphosphate (STPP) — Na5P3O10 concentrations on the physical and mechanical edible film. Randomized complete block design (RCBD) factorial was applied with three replications. The 1st factor was glycerol concentration (17.5, 22.5 and 27.5) % v/w and the 2nd factor was STPP concentration (0.1, 0.2 and 0.3) % w/v. The results indicated a significant interaction between the addition of glycerol and STPP to pH (8.12 to 8.83), thickness (0.11 mm to 0.20 mm), solubility (36.31 % to 64.44 %), tensile strength (1.20 MPa to 1.91 MPa), transparency (2.88 A546mm–1 to 3.83 A546 mm–1), and WVTR (13.27 g–1 m–2 24 h–1 to 21.23 g–1 m–2 24 h–1). According to Japanese Industrial Standard JIS Z 1707 (1975), the parameters that meet the standard was the thickness, tensile strength, and elongation