Probiotic cells support alginate-based edible film properties: study of optical, water barrier and antifungal characteristics

There is growing interest towards the functional properties and health benefits of both probiotics and paraprobiotics. In this investigation, probiotic bacterial cells (viable and non-viable Lactiplantibacillus plantarum IS-10506) were incorporated into alginate-(Alg) based edible films. Confocal laser scanning microscopy was used to confirm the presence of probiotic bacteria in the Alg matrix. The addition of probiotic cells (1 × 10⁹ cells/mL) was found to improve the performance of Alg film such as light transmission by 67.04% and antifungal activity against Botrytis cinerea by 49.54%. Although the addition of paraprobiotic cells can improve Alg film performance, particularly in terms of the water barrier property, which was confirmed with a series of assays (water vapour permeability (0.24 g.m/m².h.Pa.10⁹), hydrophobicity (67.08°) and atomic force microscopy (Ra = 5.94 nm, RMS = 7.22 nm)). Alg offered a compatible matrix for edible film containing probiotic bacteria. Alg-L film may have potential applications for protecting food products from light, and fungal decay, and Alg-D was suitable for the prevention of water loss from food.