Salmonella spp. is a major food-borne pathogen around the world. The ability of Salmonella to produce biofilm is one of the main obstacles in reducing the prevalence of these bacteria in the food chain. Most of Salmonella biofilm studies found in the literature used laboratory growth media. However, in the food chain, food residues are the principal source of nutrients of Salmonella. In this study, the biofilm formation, morphotype, and motility of 13 Salmonella strains belonging to three different subspecies and isolated from poultry houses was evaluated. To simulate food chain conditions, four different growth media (Tryptic Soy Broth at 1/20 dilution, milk at 1/20 dilution, tomato juice, and chicken meat juice), two different surfaces (stainless steel and polystyrene) and two temperatures (6 °C and 22 °C) were used to evaluate the biofilm formation. The morphotype, motility, and biofilm formation of Salmonella was temperature-dependent. Biofilm formation was significantly higher with 1/20 Tryptic Soy Broth in all the surfaces and temperatures tested, in comparison with the other growth media. The laboratory growth medium 1/20 Tryptic Soy Broth enhanced biofilm formation in Salmonella. This could explain the great differences in biofilm formation found between this growth medium and food residues. However, Salmonella strains were able to produce biofilm on the presence of food residues in all the conditions tested. Therefore, the Salmonella strain can use food residues to produce biofilm on common surfaces of the food chain. More studies combining more strains and food residues are necessary to fully understand the mechanism used by Salmonella to produce biofilm on the presence of these sources of nutrients.

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Poultry meat is a valuable source of protein for human consumption. It plays an important role in countries with poor ungulate meat production, including the Republic of Kazakhstan. The intake of fibre by the Kazakh population also remains low, while the intake of saturated fatty acids is excessive. Therefore, it is recommended to combine meat with plant products, e.g. soya flour. In the present research, we developed and evaluated a new meatball product containing different amounts of soya flour. The meatballs proved to be a semi-finished high-protein product. They also demonstrated a good fatty acid and mineral profile. The product with 30% of soya flour showed the best results: 27% of protein, low content of saturated fatty acid, and shelf life of 48 h. To extend the shelf life of the meatballs under refrigerator conditions, new disinfection methods should be developed.