ABSTRACT This research aimed to compare the coating and film‐forming properties of the bacterial alginate (BA) produced by over‐producer alginate bacteria ( Pseudomonas aeruginosa ) and brown algae alginate (AA) in the shelf life enhancement of beef thigh meat during refrigerated storage. Fourier Transform Infrared Spectroscopy (FT‐IR) spectra of bacterial alginate (BA) and AA were similar in appearance and confirmed the identity of alginate. According to Scanning Electron Microscopy (SEM) images, BA particles exhibited a rough surface, irregular polygonal structures with sharp sides and corners in comparison with AA. In contrast, AA had a smooth, more uniform surface and filamentous structure compared with BA. The AA film, with a thickness of 0.20 ± 0.04 mm, tensile strength of 41.87 ± 1.2 MPa, elongation at break of 60.53%, and Young's modulus of 102.98 MPa, exhibited significantly superior mechanical properties ( p ≤ 0.05) compared with the BA film. Also, BA‐based edible coatings significantly ( p ≤ 0.05) decreased the microbial populations (total viable count, psychrotrophic bacteria, Enterobacteriaceae , and yeast/mold), pH, and total volatile basic‐nitrogen (TVB‐N) changes of coated beef slices compared with the AA treatments during 9 days of refrigerated storage. Furthermore, sensory analyses revealed that BA groups were the most superior treatments in the stability of sensory characteristics (color, odor, and overall acceptability) of the samples. The current study results indicated that the BA coatings could significantly ( p ≤ 0.05) elongate the shelf life of refrigerated beef thigh meat up to 9 days compared to AA. These findings highlight the higher potential of BA‐based edible coating as natural and effective packaging than AA in same concentration. Therefore, considering the mechanical characteristics of AA and preserving properties of BA, it is suggested to use a mixture of these two alginates in an appropriate ratio for ideal food packaging and formulation.
Garmabaki et al. (Wed,) studied this question.