Water Vapor Permeability of Edible Films Based on Improved Cassava (Manihot esculenta Crantz) Native Starches

Starch is used in the production of edible biodegradable packaging as an attractive alternative to synthetic polymers because it is a natural biopolymer of low cost and high availability. Many studies have been carried out on films based on cassava starch and the results show that these have good flexibility and low water vapor permeability. This present research was conducted to analyse the effect of glycerol, peanut oil and soybean lecithin on the water vapor permeability (WVP) of edible films based on improved cassava (Manihot esculenta Crantz) native starches from Côte d’Ivoire. The films were prepared using 4 g cassava starch, 25% and 30% glycerol (w/w), 5% and 10% peanut oil (w/w) and 0% to 5% soybean lecithin (w/w oil) in Petri dishes. The WVP of the films was determined at 25°C and 75% relative humidity. The moisture content of the films was determined in an oven at 105°C and the film thickness was determined manually using a micrometer. The resulting films were homogeneous, transparent and crack-free. WVP, moisture content and thickness of the films increased with increasing glycerol concentration. Increasing the concentrations of the peanut oil and soybean lecithin decreased the thickness and increased the moisture content of the films. The combination of glycerol and peanut oil increased the WVP of the films, whereas addition of soybean lecithin had no effect. The lowest WVP values were obtained using 25% glycerol, 5% peanut oil and 5% soybean lecithin. Starch obtained from improved cassava varieties cultivated in Côte d’Ivoire can be a potential ingredient in the production of food packaging.