Food contamination by Salmonella poses a significant public health risk, rendering products unfit for consumption. This study aimed to evaluate the efficiency of ozone gas (O₃), applied in flow and at low pressures, in inactivating Salmonella on black peppercorns (Piper nigrum L.). Samples were inoculated with a cocktail of four Salmonella serotypes and subjected to ozonation under flow or low-pressure conditions in a hypobaric chamber. For the flow treatment, ozone gas at 16 mg L⁻¹ was humidified by passing it through a 40% (w/v) sodium chloride solution and applied for 2, 4, and 8 h. For the hypobaric chamber treatment, an inlet O₃ concentration of 60 mg L⁻¹ was used, with 10, 15, and 20 injections. The results showed that, under flow ozonation for 8 h, Salmonella was absent in 25 g of the sample. Ozone treatment increased pH, total titratable acidity (TTA), antioxidant activity (DPPH*), lightness (L*), color saturation (C*), total phenolic content (TPC), and the concentration of major essential oil compounds in all treatments. Under low-pressure ozonation, Salmonella persisted in all tested conditions, along with changes in color difference (∆E*), moisture content, TTA, DPPH*, L*, C*, pH, TPC, and the concentration of major essential oil compounds. The essential oil yield was not affected. Although the application of ozone at low pressures reduced Salmonella contamination, it was not sufficient for complete inactivation under the tested conditions. However, the flow-applied ozone treatment proved effective in the inactivation of Salmonella in black peppercorns.

This study aimed to investigate the effectiveness of ozonated water in the sanitation and postharvest quality of acerola fruits. The experiment comprised seven treatments: a control group with untreated fruits, three different durations of exposure to ozone microbubbles (20, 40, and 60 min), and three different durations of exposure to ozone-free microbubbles (20, 40, and 60 min). Acerola fruits were stored in a refrigerated environment below 5 °C at 87% relative humidity. Microbiological and quality analyses were performed immediately after ozonation on day 0 and then on storage days 3, 6, and 9. The quality parameters assessed included the fresh mass loss percentage, firmness, soluble solid content, pH, total titratable acidity, vitamin C, color, total phenolic compounds, and total antioxidant activity. The use of ozonated water was found to effectively maintain the firmness of the acerolas, regardless of the exposure duration. Changes were observed on the surface of fruits treated with ozone microbubbles, especially when 60 min of exposure was adopted. Treating acerolas with ozone microbubbles for 20 min proved to be the best condition for inactivating bacteria and fungi and preserving the vitamin C, pH, total titratable acidity, total phenolic compounds, and total antioxidant activity of the fruits throughout storage. In conclusion, ozonated water is a promising technology for sanitizing and preserving the postharvest quality of acerola.