Determination of the preservative effectiveness of a natural additive prepared with propolis and Alchemilla persica in a model food product

In this study, the potential of propolis and Alchemilla persica, known for their natural antioxidant and antimicrobial properties, was evaluated in mayonnaise formulations. It has been demonstrated that these ingredients can be an alternative to traditional preservatives and make the model product functional, shelf-stable and safe. Physicochemical and rheological analyses indicated that the natural extracts positively contributed to emulsion stability. All samples exhibited pseudoplastic flow behavior, which is favorable for spreadability and texture, suggesting that the formulations are suitable for commercialization. Microscopic observations confirmed a homogeneous dispersion of the oil phase within the aqueous phase, indicating successful emulsion stabilization and effective integration of the natural additives. During the storage period (0, 30, 60, and 90 days), pH, total acidity, free fatty acids, and oxidation indicators (peroxide and p-anisidine values) were monitored. Formulations containing propolis demonstrated a notable reduction in oxidative degradation. In the Rancimat analysis, the MP-3 sample containing 0.3% propolis exhibited the highest oxidative stability (14.71 hours), highlighting propolis's preservative effect at appropriate concentrations. Regarding antioxidant capacity and phenolic content, the MAP-3 sample stood out, displaying the highest levels of total phenolics and DPPH radical scavenging activity. The combined use of propolis and Alchemilla persica at 0.3% showed a synergistic effect, significantly enhancing the bioactive value of the product. Microbiological evaluations showed that all samples complied with TS 9777 mayonnaise standards, with no detection of Salmonella spp. The natural additives did not adversely affect microbial safety. Cell viability assays (XTT) revealed significant differences among formulations in terms of cytotoxic and proliferative effects. MP-1 and MP-3 exhibited cytotoxicity at high concentrations, whereas MAP-3 showed proliferative effects at low concentrations (149.07% cell viability at 500 ppm). This suggests that low doses of natural additives may promote cell proliferation, though further studies are needed to understand the underlying mechanisms. In sensory evaluations, the commercial sample received the highest overall acceptance. Propolis-containing samples were rated similarly to the control in terms of appearance, although some plant extracts negatively affected the traditional mayonnaise color, leading to slightly lower scores. Overall, the combined use of propolis and Alchemilla persica extract in mayonnaise demonstrated the feasibility of producing natural, functional, antioxidant-rich, and microbiologically safe emulsified products. These natural additives offer promising potential as alternatives to synthetic preservatives in the development of functional foods.