Ready-to-eat food products can be readily consumed without further preparation and are convenient for busy on-the-go consumers. The objective of the study was to assess the microbiological quality of ready-to-eat salads. Thirty RTE salads were tested for the presence of bacteria, yeasts, and molds using the TEMPO and agar plate method. The study demonstrated that most of the tested products were characterized by varying microbiological quality. The total number of mesophilic microbiotas was about 6 log CFU g⁻¹. The high number of microorganisms was due to yeast and molds or Enterobacteriaceae. Half of the salads were contaminated with E. coli and three salads were contaminated with S. aureus. LAB were also found, which can be explained mainly by a dairy ingredient. In some salads, Salmonella spp. and L. monocytogenes were detected (26.7% and 33.3% of the samples, respectively). Based on the conducted tests, it was found that the microbiological quality was not satisfactory. The results presented in this study indicate that there is a significant problem of the presence of pathogens. Manufacturers should strive to reduce the possibility of microbial contamination through the use of widely understood hygiene of the production process, using hurdle technology, including the modified atmosphere and refrigerated storage.

The control of spoilage microorganisms and foodborne pathogens in meat and meat products is a challenge for food producers, which potentially can be overcome through the combined use of biopreservatives, in the form of a mix of various microbial hurdles. The objective of this work is to systematically review the available knowledge to reveal whether various microbial hurdles applied in combination can pose an effective decontamination strategy for meat and meat products. PubMed, Web of Science, and Scopus were utilized to identify and evaluate studies through February 2023. Search results yielded 45 articles that met the inclusion criteria. The most common meat biopreservatives were combinations of various starter cultures (24 studies), and the use of mixtures of non-starter protective cultures (13 studies). In addition, studies evaluating antimicrobial combinations of bacteriocins with other bacteriocins, BLIS (bacteriocin-like inhibitory substance), non-starter protective cultures, reuterin, and S-layer protein were included in the review (7 studies). In one study, a biopreservative mixture comprised antifungal protein PgAFP and protective cultures. The literature search revealed a positive effect, in most of the included studies, of the combination of various bacterial antimicrobials in inhibiting the growth of pathogenic and spoilage bacteria in meat products. The main advantages of the synergistic effect achieved were: (1) the induction of a stronger antimicrobial effect, (2) the extension of the spectrum of antibacterial action, and (3) the prevention of the regrowth of undesirable microorganisms. Although further research is required in this area, the combination of various microbial hurdles can pose a green and valuable biopreservation approach for maintaining the safety and quality of meat products.

Probiotic strains used in the production of dry fermented meat should have appropriate technological properties comparable to traditional starter cultures used in meat processing. The problem arises when probiotics are added to a nonsterile food matrix, such as meat, and when it is uncertain whether these microorganisms have dominated the environment. The study aimed to assess the microbiological, physicochemical quality and safety of dry fermented pork loins and sausages with the addition of the probiotic starter culture LOCK900, produced under industrial conditions. Additionally, genetic identification by the PCR method and the presence of LOCK900 in the final products and after storage was done. It was demonstrated by the high number of LAB (>6.0 log cfu g ⁻¹) and confirmed the presence in 90% of the probiotic strain LOCK900 in the study of dry fermented meat products during all processing stages. Moreover, the safe and good quality loins and sausages can be stored in refrigerated, anaerobic conditions for 12 weeks, provided that optimized technological conditions are applied. In conclusion, the obtained results of the experiment showed that it is possible to create innovative functional dry fermented pork loins and sausages in a laboratory and then transfer the developed technology to full industrial conditions.

The aim of the work was to apply the bacteria Staphylococcus carnosus ATCC 51365 in the meat curing process with the use of a reduced amount of sodium nitrite and to evaluate the effects of bacteria on residual nitrites and nitrates, the content of nitrosyl pigments, colour, pH, oxidation-reduction potential, microbiological, and the sensory quality of a cooked meat product. Three meat batters in cans were prepared: (C) a control batter cured with NaNO₂—100 mg/kg, (L) a batter cured with NaNO₂—15 mg/kg, and (LS) a batter cured with NaNO₂—15 mg/kg and S. carnosus (10⁷ CFU/g). The cans were stored at a temperature of 4°C for 24 h (curing time) and cooked. The analysis was carried out after production and after 4 and 8 weeks of storage. The use of denitrifying bacteria in the curing process with a reduced amount of sodium nitrite increased the availability of nitrite in the meat, by reducing nitrates formed as a result of a dismutation reaction. The reaction contributed to the formation of nitrosyl pigments in a larger quantity than in the treatment in which the denitrifying bacteria were not used. The LS treatment was characterized by the greatest redness. The colour of the LS treatment was stable during storage. No negative effect of S. carnosus on the sensory quality of the meat product was found. The use of S. carnosus had no influence on the microbiological quality of meat product during storage.

The aim of this research was to evaluate the effect of acid whey on changes in the fatty acid profile, oxidative stability, physico-chemical parameters, and microbiological and sensory quality of traditional organic uncured fermented Polish bacon after production and during chilling storage. Three different treatments of fermented bacon were produced: C—control bacon with a nitrite curing mixture; T—bacon with a nitrate curing mixture; and AW—bacon with acid whey and NaCl. The acid whey used in the production of uncured fermented pork bacon positively changed the sensorial characteristics, directly after the ripening process, and had a positive effect in terms of a decrease in the pH of the product. All of the fermented bacon treatments in general were of good microbiological quality. A higher lactic acid bacteria (LAB) level was observed in the AW treatment after the fermentation process, and the bacteria number did not change during storage, whereas in the C and T treatments, the LAB level increased during storage (p < 0.05). The application of acid whey did not limit the formation of secondary oxidation products (TBARS) during bacon ripening (1.68 mg MDA kg⁻¹), but had a reduced value during storage time (0.73 mg MDA kg⁻¹). The highest polyunsaturated fatty acid (PUFA) levels, after ripening and after four weeks of refrigerated storage, were found in the C treatment. In the AW treatment, it was found that the PUFA level increased; likewise, the content of n-3 and n-6 fatty acids increased, while saturated fatty acids (SFAs) decreased during storage (p < 0.05). The opposite tendency was observed in the C treatment. After four weeks of storage, the PUFA/SFA ratio was the lowest in the nitrate treatment, and higher values of the PUFA/SFA ratio were obtained in the acid whey and nitrite treatment (p < 0.05).

The aim of this study was to determine the impact of environmental conditions on the antimicrobial properties of 21 lactic acid bacteria strains in the selected indicator bacteria. To assess the antimicrobial activity of the whole bacteria culture (WBC), the agar well diffusion method was used. The interference of LAB strains with the growth of the selected indicator bacteria was evaluated by incubating co-cultures in the food matrix. Based on the conducted research, it was found that environmental conditions have a significant impact on the antimicrobial activity of lactic acid bacteria strains. The highest antimicrobial activity was recorded under optimal conditions for the development of LAB, the incubation time being different depending on the indicator strain used. The tested LAB strains were characterized by a high ability to inhibit indicator strains, especially in the food matrix. These results led us to further characterize and purify the antimicrobial compound produced by lactic acid bacteria taking into account changing environmental conditions.