Effect of lactic acid bacteria on the textural properties of an edible film based on whey, inulin and gelatin

This study was aimed to evaluate the effects of different components and the addition of probiotic bacteria of lactic acid bacteria (LAB, Lactobacillus casei) on the physicochemical and textural characteristics of edible films using a response surface Box-Behnken design. The edible films were made of the following components: Whey (8%), glycerol (6%), inulin (0 to 4%), gelatin (2 to 5%) and probiotics (0 to 2%). The addition of LAB significantly affected the pH, viscosity, luminosity, hardness and Young's modulus of the films. However, all formulations presented physicochemical and textural characteristics suitable for the survival of lactic acid bacteria during storage. Formulas 10 and 3 with a composition of 2% inulin, 3.5% gelatin and 1% probiotic, demonstrated higher responses to pH, viscosity, luminosity, hardness and Young's modulus, whereas formulas 14 and 12 exhibited lower responses to the above-mentioned features but proved the most resilient. Therefore, edible films with added probiotic bacteria could be applied to a variety of foods and to increase consumer choice.Keywords: Edible film, lactic acid bacteria, inulin, gelatin, wheyAfrican Journal of Biotechnology Vol. 12(19), pp. 2659-2669