Optical interferometric: A novel approach for sensitive cost-effective measurement of multispecies biofilm from stress-tolerant field samples.

Biofilms significantly impact public health and food safety within the meat industry. Detecting and quantifying biofilms are crucial tasks; however, their inherent complexity and heterogeneity, particularly in immature stages, present substantial challenges. Innovative techniques are necessary for accurate biofilm measurement, despite the presence of diverse interfering agents. An assessment of multispecies biofilms from cattle abattoir environmental samples (wall, basin, and door), equipment (tub, knives, and swivel), and offal (heart, lung, liver, spleen, rumen, and intestine). To elucidate the complexities of biofilm formation, a dual-pronged approach was employed, utilizing epifluorescence microscopy and optical interferometry to conduct a comprehensive analysis of biofilms that had developed on two distinct types of surfaces. Specifically, biotic surfaces that had undergone chilling and abiotic surfaces subjected to chlorination were examined to gain a deeper understanding of the structural and compositional characteristics of these microbial communities. Additionally, the presence of antibiotic-resistant bacteria within the submerged biofilm was evaluated. Despite chilling, the multispecies biofilm continued to grow from 0.2 μm to a maximum of 1.75 μm on the beef spleen surface, demonstrating the interplay of different bacterial species in biofilm formation on biotic surfaces. The highest antibacterial resistance was recorded for Staphylococcus simulans, followed by Staphylococcus saprophyticus and Staphylococcus aureus. In conclusion, the optical interferometer is a straightforward, fast, and sensitive technique for measuring biofilm thickness within the range of 0.1 to 4 μm. Progress in this field can revolutionize food safety, hygiene, biosecurity, and biomedical applications.