Food labelled with a “best before” date has a long shelf life. This study aimed to examine the respondents’ knowledge and understanding regarding the labelling on food products, as well as to assess the microbiological, physico–chemical and the sensory quality of selected durable food products on and after the date specified by the manufacturer. Two methods were used—a survey and laboratory tests. It was found that the majority of respondents have difficulty distinguishing and understanding the terms on the label and that a significant proportion of the respondents consume food products after the “best before” date. Laboratory tests of milk, pasta, mayonnaise and jam confirmed the microbiological safety of the products even six months after the “best before” date. Other features (texture, colour and sensory quality) slightly changed after one month for milk and mayonnaise (the colour had become more yellow) and after three months for pasta (its hardness had decreased) and jam (it had become browner). The possibility of extending the “best before” dates of selected durable foods could be considered, which could allow such products to legally be handed over to public benefit organisations, thereby reducing food wastage.

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.

Twenty-nine Lactobacillus plantarum strains isolated from different types of Polish regional cheeses (Oscypek and Korycinski) were assessed for selected probiotic properties and anti-staphylococcal activity. Most of the tested L. plantarum strains were considered safe. Whole bacterial cultures (WBC) and cell-free supernatants (CFSs) of L. plantarum strains inhibited growth of Staphylococcus aureus (average inhibition growth zones were 2.8 mm ± 1.2 and 2.8 mm ± 1.1 respectively). Moreover, almost all neutralized, catalase-treated cell-free supernatants (CFN) of L. plantarum cultures also exhibited slight anti-staphylococcal activity in vitro. The most promising strains Os4 and Kor14 were selected for further study. Both strains were able to survive during digestive gastro-intestinal passage model. Live cells of L. plantarum Os4 and Kor14 caused the strongest inhibition of S. aureus adhesion to Caco-2 cells comparing with CFN and heat-killed bacterial cells. S. aureus and L. plantarum (Os4 or Kor14) co-cultured in skim milk resulted in growth inhibition of S. aureus in both 8 °C and 37 °C incubation temperatures. Observed abilities, demonstrated for L. plantarum Os4 and Kor14, confirms that these strains could be used in the food industry as protective cultures.

The study aimed to develop the high-protein bars using organic ingredients such as whey protein concentrate (WPC), prebiotic-inulin, as well as pro-health additives (dried fruits, cereals, and nuts). The physicochemical, microbiological, sensory, and consumer evaluation of ingredients and final products were made. The musli (M), pumpkin (P), and coconut (C) bars were developed including three different flavors for each bar. The novel products were found to be a good source of protein and fiber. The M and P3 bar samples contained >10 g of fiber/100 g of product. The M and C bars contained over 20 g/100 g proteins in total, while P bars contained 17.3–19.1 g/100 g of protein. The antioxidant activity of bars was proportional to the fruit content. The water activity was varied (0.63–0.74), while pH value ranged from 6.3 to 7.0. Microbiological quality of ingredients and bars were good, though in M and P bars, the presence of Bacillus cereus was found. The C bars found the highest marks of the overall quality. The newly developed high-protein products can be used in rational nutrition of a wide group of people who are health-conscious.