Impact of in-package cold plasma treatment on the physicochemical properties and shelf life of button mushrooms (Agaricus bisporus)

Abstract

Button mushrooms are perishable due to microbial spoilage and browning. The effect of in-package cold plasma CP treatment on the quality and shelf life of button mushrooms is presented. Samples were sealed inside a package with different gas combinations [80% O2 + 10% CO2 + 10% N2, 10% O2 + 10% CO2 + 80% N2, and 10% O2 + 80% CO2 + 10% N2], treated with CP for 15 min at 28 kV and stored at 4 °C for 7 days. Microbiological and physicochemical properties of button mushrooms (control, samples treated with direct cold plasma (DCP), and those packed in three different modified atmospheric packing (MAP) compositions) were analyzed on days 1, 4, and 7 after treatment. Following DCP and in-package CP treatment, the total bacterial count was reduced by 0.93 and 1.14 log CFU/g, while the yeast and mold count was reduced by 1.07 and 1.24 log CFU/g, respectively. In-package CP reduced PPO activity by 29%. Changes in physicochemical properties of button mushrooms were insignificant on day 1. MAP with high oxygen showed larger microbial reductions than the other two gas combinations. At the end of storage, all in-package CP treated button mushrooms maintained significantly (p < 0.05) better quality characteristics than control and DCP-treated mushrooms. The samples treated with CP and kept in a high O2 gas concentration exhibited better quality characteristics. Therefore, in-package CP technology with high O2 concentration can be used as a potential tool for the decontamination and shelf-life extension of button mushrooms.