Development and characterization of edible biofilms based on mucilage of Opuntia ficus-indica and Locust Bean Gum from Tissemsilt region in Algeria

Abstract

The development of biodegradable edible films/food packaging is in the core of the new management strategies of food handling. The great challenge facing the food industry today is innovation in terms of ecological and effec-tive edible coatings, with improved mechanical and sensory qualities but at lower cost. The current study intends to develop and characterize edible films by combining crude and pure Opuntia cladode mucilage and Locust Bean Gum (LBG), then evaluate their coating effect on stored strawberry fruits. The films were formulated using the two polymers at the same con-centration (2% mucilage / 2% LBG) and glycerol as plasticizer, and they were compared for their physicochemical and mechanical properties like thick-ness, moisture content, water vapor transmission and transparency. The pH, weight loss and sensorial qualities of coated strawberries stored at 4°C were assessed during 14 days. The obtained results have shown that for the crude composite films CM-CLBG the thickness, moisture and water solubility were higher compared to those of PM-PLBG where water vapor permeability (WVP), transparency and surface contact angle (hydrophobicity) displayed the highest values. Weight loss and drop in pH of strawberries soaked in the CM-CLBG and PM-PLBG coating solutions and stored at 4°C were less signifi-cant than those of uncoated strawberries. Otherwise, coated fruits pre-served a marketable visual appearance and texture, but lost their redness and gloss after the storage period. Despite the promising potential of Opun-tia mucilage/LBG formulated films, some improvements are still needed to solve the problem of fruit appearance and meet marketing standards.