Optimizing conditions for the development of a composite film from seaweed hydrocolloids and pectin derived from a fruit waste, gac pulp

Recently, edible films and coatings have received more attention instead of plastic packaging. Pectin prepared from gac pulp, a waste generated from gac oil production, was used to prepare edible films combined with seaweed hydrocolloids. This study aimed to investigate the impact of sodium alginate (SA), kappa-carrageenan (KC), and gac pulp pectin (GPP) on the physical, barrier, and mechanical properties of the resultant films. The optimum formula with the best characteristics was identified using Response Surface Methodology (RSM). Results revealed that most of the film properties were significantly influenced by seaweed hydrocolloids, while GPP significantly affected color properties. Besides, the interaction between GPP and seaweed hydrocolloids affected the water vapor permeability and mechanical properties. The optimum formula was SA of 1.28% w/v, KC of 0.58% w/v, and GPP of 0.25% w/v. The result suggests that this formula has the potential as an edible film for further applications in foods. Novelty impact statement: A composite edible film with great physical and mechanical properties can be developed from an optimal formulation of sodium alginate, kappa-carrageenan, and gac pulp pectin, derived from a waste of the oil production. This film is potentially applied for coating and preservation of foods to improve their properties and shelf-life.