Production and Evaluation of Fruit Vinegar with Anti-Helicobacter pylori Activity as a Sustainable Approach to Reducing Post-Harvest Losses

Vinegar is a widely used fermented food product, known for its preservative, sensory, and functional properties. This study aimed to produce fruit vinegars from fig, peach, and prickly pear using kombucha as a starter culture, with the dual purpose of developing value-added functional products and reducing post-harvest fruit losses. The produced vinegars were evaluated for their physicochemical properties, bioactive compounds, mineral composition, organic acid profile, antioxidant activity, and anti-Helicobacter pylori potential. The results showed significant differences among the fruit vinegars. Fig vinegar (FV) exhibited the highest total phenolic content (609.58mg GAE L-1), flavonoids (255.87mg catechin L-1), and antioxidant activity (82.51%), respectively. Peaches vinegar (PV) was characterised by the highest potassium content, while prickly pears vinegar (PPV) showed the highest calcium concentration. HPLC analysis revealed that acetic and lactic acids were the predominant organic acids in fig vinegar, whereas malic and gluconic acids were dominant in peach and prickly pear vinegars, respectively. Furthermore, all vinegar samples demonstrated notable anti-Helicobacter pylori activity. Fig vinegar showed the strongest antibacterial effect, with minimum inhibitory and bactericidal concentrations (MIC and MBC) of 125 µg mL⁻¹. All analyses were performed in triplicate, and the results were statistically analysed and expressed as mean ± standard deviation. Overall, this study demonstrates that fruit vinegars produced using kombucha can serve as technologically feasible and functional food products with antioxidant and antibacterial properties, offering a sustainable approach for valorising surplus fruits and supporting industrial applications in food processing..