Extending the shelf-life of Lentinula edodes: the interplay between ozone dosage, bacterial dynamics, and physicochemical stability.

This study evaluated the effects of ozone (O₃) on the population dynamics of aerobic mesophilic microorganisms and the preservation of the physicochemical quality of mushrooms (Lentinula edodes) during storage. Samples of 100 g were treated with O₃ at nominal concentrations of 5.00, 10.00, and 15.00 mg·L-1, at a constant flow rate of 2.00 L·min-1 and an exposure time of 15 min. For the concentration of 15.00 mg·L-1, a reduced time of 7.3 min was additionally evaluated. Untreated mushrooms were used as a control. The concentration of O₃ inside the chamber was continuously monitored during ozonation. The internal fraction of O₃ was dependent on the inlet concentration and exposure time, reaching after 15 min, 65.30% and 61.30% of Cₑₙₜ for 5.00 and 10.00 mg·L-1, and up to 87.10% of Cₑₙₜ for 15.00 mg·L-1. The application of 15.00 mg·L-1 of O₃ for 7.3-15 min promoted a reduction in microbial load of up to 2.52 ± 0.28 log CFU·g-1. The Gompertz model showed an increase in λ from 0.41 d (control) to 4.73 d at 15.00 mg·L-1-7.3 min and to 1.81 d at 15.00 mg·L-1 -15 min, with a reduction of up to ~84% in μmax, evidencing persistent microbial inhibition during storage. O₃ did not affect pH (p > 0.05) and limited mass loss and color degradation over 12 d at 7 °C. The efficiency of O₃ was determined by the combination of concentration and exposure time, with a direct impact on microbial inactivation and product stability during storage.