Formulation and stability of biodegradable films made from cellulose, pectin, and bee bread oil

Abstract

Polymers that are biodegradable, environmentally safe, and edible are produced from

sustainable and edible ingredients like lipids, polysaccharides, and proteins, and degrade faster than non-renewable petroleum-based polymeric compounds [1]. Cellulose, starch, and chitosan are natural sources

of polysaccharide that can be used as an edible film in agricultural products to extend the shelf life of fresh fruits and vegetables, reduce oil/fat absorption in fried food, and prevent food flavor loss [1,2]. The aim of this study was to produce films from carboxymethyl cellulose (CMC), pectin, bee bread oil (BBO), and

glycerol in order to determine some mechanical and physicochemical parameters (e.g., oxygen permeability, color, thickness) of obtained films. The thickness of the film is a major characteristic that determines other properties (such as optical, barrier, mechanical, and thermal properties) of the films that have been developed. The highest value of thickness (63.2 μm) was obtained for control sample (CMC), while the lowest value (54.4 μm) was recorded for sample formulated with 1% bee bread oil (CMC + 10% P + 1% BBO). It can be explained

by the fact that CMC is able to form ionic bonds with ionic polysaccharides like pectin because of its anionic structure [1]. The OP of prepared films decreased with the addition of 1% BBO (0.78 cc × mm/m2 × atm × day) but increased after addition with higher concentrations of BBO (0.84 cc × mm/m2 × atm × day). OP values in the case of 2 and 3% BBO films can be explained by the fact that essential oil influenced the polymeric matrix, dynamics, and statics of polysaccharides used in film formulation. L* values decreased when BBO was incorporated into the CMC films, while the h*ab values ranged between 5.8 and 345.4; all developed films were ascribed to the red color. Additionally, principal functional groups and interaction between CMC, P, and BBO were observed by FT-IR spectroscopy. Conclusions. BBO can easily be incorporated into polymer aqueous solutions to obtain cast films. The CMC + 10% P + 2% BBO film showed best results in all the characterizations. The results showed that values for OP were lower for films incorporated with BBO in comparison with control sample. Therefore, these films are suitable for application in food industry in which a high oxygen barrier is needed.