Development and characterization of edible films based on carboxymethyl cellulose enriched with pomegranate seed oil and the coating of strawberries

Abstract

The cellulose-based polysaccharide edible film enriched with pomegranate seed oil was characterized and used for the coating of strawberries to determine the effects on their quality over shelf life. Edible bioactive films were prepared with carboxymethyl cellulose (CMC) which contained different concentrations (0.1, 1, 2, and 3%) of pomegranate seed oil (PSO). It was found that the opacity and roughness of films increased with the increasing concentration of PSO. The FTIR spectra results with a lower transmittance of the –OH stretching band at around 3350 cm−1, showed that the hydrophobic nature of the films increased where the moisture absorption of the bioactive films decreased with the addition of pomegranate seed oil. The weight loss of the coated strawberries decreased 35% less than the control at the end of the 16 d of storage period at 5 ± 1°C. The total phenolic content of the strawberries was preserved with the coating process at the level of 70%. Pomegranate seed oil-enriched CMC edible coatings showed promise as a tool for quality maintenance of strawberries. Practical applications Edible films and coatings are bio-based, environmentally friendly technologies that have the potential to extend the shelf life of fruits and vegetables, reduce microbial spoilage, and preserve their unique flavor. CMC is a colorless, tasteless, non-toxic, non-allergenic, and odorless anionic polysaccharide and is widely used as an edible coating material. Strawberries, which are potential raw materials for edible coating applications, have a very short shelf life. Various applications such as cold storage, chemical preservatives, and modified environmental packaging have been developed to preserve the quality of strawberry fruit and extend its shelf life. However, many of these uses have a detrimental effect on aroma, color, texture, or flavor. For this reason, the use of CMC is an alternative to increase the shelf life of strawberries and to preserve their quality properties during storage. In addition, the use of various essential oils will increase the effectiveness of the application.