A well balanced diet of modern population includes an increased consumption of products from goat’s milk, which has composition different from the commonly used cow milk. Goat’s milk is characterized by better digestibility, higher...

The aim of the study was to assess the antibacterial properties of bioactive compounds released during the fermentation of goat’s milk by selected bacterial strains that are part of the kefir grain microflora. The material used in the experiments was kefir grain microflora (Lactobacillus kefiranofaciens subsp. kefirgranum DSM 10550, Lactobacillus kefiri PCM 2501, Lactobacillus parakefiri DSM 10551, Lactobacillus brevis PCM 488, Lactobacillus delbrueckii subsp. lactis PCM 2611), goat’s and cow’s milk and whey from these kinds of milk. The antimicrobial activity was tested against E. coli, Salmonella, Micrococcus luteus and Proteus mirabilis. Based on the experiments, it was found that during the fermentation of whey and goat's milk, bioactive substances were released, which inhibit the growth of indicator microorganisms by up to 8 logarithmic cycles.

The aim of the study was to assess the antioxidant potential of goat’s milk and whey from goat’s milk fermented with selected bacteria strains from kefir grain (L. plantarum, L. fermentum, L. rhamnosus and L. acidophilus) with regard to fermented cow’s milk with the same bacteria strains. The assessment of antioxidant potential was made by ABTS, DPPH, TPC and FRAP methods. The work also assessed metabolic activity of tested lactic acid bacteria using measurement of electrical impedance changes in the growing medium. The highest values describing the antioxidant potential were found for fermented milk by L. acidophilus. It was also found that the time of cooling storage causes significantly increasing the antioxidant potential of most analyzed samples. Metabolic activity of tested lactic acid bacteria was the highest for cow’s milk. The course of curves for goat’s milk and whey from goat’s milk was similar, which confirms the differences between cow and goat milk.

The aim of the study was to investigate the effect of modified lysozyme on the microflora, physicochemical and sensory characteristics of pork loin packaged in modified atmospheres and stored at 4 ± 1 °C. Different gas compositions (M1 65:25:10 O₂:CO₂:N₂; M2 50:40:10 O₂:CO₂:N₂; M3 80:20 O₂:CO₂) were used. The microbiological parameters (APC, Enterobacteriaceae, Pseudomonas spp., lactic acid bacteria), physicochemical indexes (pH, colour) as well as a sensory attribute, i.e., aroma were analysed. Meat samples were tested after five, 12, 19, 23, and 28 days of storage. Changes in the qualities of pork were determined throughout the storage. The proportions of polymeric forms, hydrolytic activity and hydrophobicity were determined in the lysozyme preparation. Modified lysozyme exhibited higher hydrophobicity and lower hydrolytic activity than lysozyme monomer. The colour parameters L* and a* were not considerably affected by the addition of modified lysozyme. The sample with the modified lysozyme was given the highest score for aroma. In comparison with the monomer, the modified lysozyme exhibited greater antibacterial effect, especially against Pseudomonas and Enterobacteriaceae. Microbial growth rates in the sample with modified lysozyme, packaged in an atmosphere with the highest content of CO₂ (total plate count 4.59 log CFU/cm²; moulds and yeasts 2.17 log CFU/cm²) were lower than those observed in the sample without lysozyme packed under M1 and M3 (20−25% CO₂). The use of an atmosphere with gas composition and modified lysozyme considerably extended the shelf life of pork. The combination of the atmosphere with the highest content of carbon dioxide (50% O₂, 40% CO₂, 10% N₂) and modified lysozyme resulted in the best effect. This strategy extended the shelf-life by more than 20%, as compared with the control sample without lysozyme, packaged in an atmosphere of 50:40:10 O₂:CO₂:N₂.

The aim of the study was to assess the antibacterial features of functional macromolecules released during the fermentation of goat milk and whey from goat milk by selected lactic acid bacteria strains that are components of kefir grain microflora. Two milk sources were used: goat milk and whey from goat milk. The lactic acid bacteria (LAB) and indicator microorganisms used were Lactobacillus plantarum PCM 1386, Lactobacillus fermentum PCM 491, Lactobacillus rhamnosus PCM 2677, Lactobacillus acidophilus PCM 2499, Escherichia coli PCM 2793, Salmonella enteritidis PCM 2548, Micrococcus luteus PCM 525, and Proteus mirabilis PCM 1361. The metabolic activity of LAB was described by the Gompertz model, and the parameters proposed for this experiment were the maximum rate of change of electrical impedance and potential biodegradability. Antibacterial activity was examined using the culture method in a liquid medium, determination of the reduction in indicator microorganisms, and optical density changes. Results show that the selective LAB produced certain active biomolecules with antibacterial activity from whey, a by-product that is sometimes troublesome for goat milk processors to manage. Lactobacillus acidophilus is a microorganism that is characterized by the highest metabolic activity in goat milk and whey from goat milk. It has the possibility to produce macromolecules with antibacterial activity.

The aim of this study was to identify the most common threats and non-compliances occurring during the production of unpasteurized fruit juices in relation to the requirements of the IFS standard. Additionally, this study aimed to demonstrate how the IFS standard supports the introduction of sustainable practices in the production of fruit juices. The research material was data from internal audits conducted in three plants producing unpasteurized fruit juices and final product microbial assessment and swabs from the production environment taken from the three plants. These plants are located in western Poland. Based on the assessment carried out, it was found that most non-compliances were identified in the areas covered by prerequisite programs, but the final product and production environment met product and production safety requirements. It was also stated that the corrective actions proposed and approved by the auditors correct the existing non-compliance without the aspect of continuous improvement. The research and audits carried out as part of this work allowed us to conclude that international standards, such as the IFS, are an excellent tool for introducing the principles of a sustainable approach to production plants.