Comprehensive dynamics of bacterial and fungal diversity throughout concentrated chicken broth processing: Integrating culture-dependent and independent techniques.

This study presents comprehensive insights into the microbiological profile across all concentrated chicken broth processing stages, utilizing a combination of amplicon sequencing based on metataxonomic and culturing techniques. Samples were systematically collected throughout the production chain, with each batch yielding 10 samples per day across eight different dates. These samples underwent thorough analysis, including 16S rRNA and ITS sequencing (n = 30), culture-dependent microbiological tests (n = 40), and physical-chemical characterization (n = 10). Culturing analysis revealed the absence of Listeria monocytogenes and Salmonella spp. at any stage of processing, counts of various microorganisms such as molds, yeasts, Enterobacteria, and others remained below detection limits. Notably, spore counts of selected bacterial groups were observed post-processing, indicating the persistence of certain species, including Bacillus cereus and Clostridium perfringens, albeit in low counts. Furthermore, the study identified a diverse array of bacterial and fungal species throughout the processing chain, with notable occurrence of spore-forming bacteria. The presence of spore-forming bacteria in the final product, despite thermal processing, suggests the need for enhanced strategies to mitigate their introduction and persistence in the processing premises. Thus, this study offers valuable insights into microbial dynamics and diversity through processing concentrated chicken broth.

Correlation between natural microbial load and formation of ropy slime affecting the superficial color of vacuum-packaged cooked sausage.

The present study outlines a comprehensive correlation between the natural microbial load, which is predominantly composed of heat-resistant sporous-forming Bacillus, and the changes in the original properties related to the superficial color of vacuum-packaged cooked sausages. For this purpose, microbial growth curves were plotted by stimulating the growth of the natural microbiota in sausage packages at different temperatures. The correlations were investigated during sample incubation by the instrumental evaluation of color and the ropy slime detection on the sausage surface. The entrance of the natural microbiota into the stationary phase (ca. 9.3 log cfu/g) resulted in changes in the superficial color, which was demonstrated by the discoloration of vacuum-packaged cooked sausages. Therefore, it seems to be a suitable borderline for predictive models applied in durability studies that aim to estimate the period in which vacuum-packaged cooked sausages keep their typical superficial color, anticipating product refusal in markets.