Effect of cold atmospheric plasma torch distance on the microbial inactivation and sensorial properties of ready-to-eat olivier salad

Abstract

This study aimed to investigate the effect of the cold atmospheric plasma torch (CAPT) nozzle distance from the surface of Olivier salad and the treatment time in the reduction of microbial load and sensory properties of the product simultaneously. In this study, the CAPT nozzle was placed at 3, 5, and 7 cm distances from the surface of the Olivier salad, and its efficiency in inactivating the microbial population, decimal reduction time (D-value), and sensory evaluation of the product were evaluated. The results showed that reducing the distance and increasing the plasma treatment time (30, 60, 90, and 120 s) both reduced the microbial load of the product. The maximum inactivation and the minimum D-value are related to the 3 cm distance for 120 s, which has been 3.77, 2.91, and 1.52 log CFU/g for Coliform, Total viable count (TVC), mold and yeast, respectively. The lowest D-value was related to Coliform (4.41 s). CAPT treatment had no significant sensible effect on the product's sensory characteristics compared to the control sample. The treated sample at a 3 cm distance for 90 s and the microbial reduction to an acceptable amount and high acceptancy from sensory evaluators were selected as the superior treatment in this study. Also, the results showed that CAPT could be used successfully in ready-to-eat (RTE) products.

A review on mechanisms and impacts of cold plasma treatment as a non‐thermal technology on food pigments

“…Cold Plasma is a cutting‐edge, newly emerging technology that acts as a surface agent and has fewer degrading effects on food quality and nutritional value than conventional processes (Moradi et al., 2023 ; Pankaj et al., 2014 ). In the food industry, CP has been used for decontamination (Gavahian & Khaneghah, 2020 ; Ramezan et al., 2023 ; Wang et al., 2020 ), enzyme inactivation (Mir et al., 2020 ; Thirumdas & Annapure, 2020 ), and more recently CP has demonstrated significant dehydration potential (Ashtiani et al., 2020 ; Zhou et al., 2020 ). Although the exact mechanism of inactivation by plasma treatment is still unknown, the main proposed mechanism is the impact of reactive species like ROS and RNS induced by plasma on the cell wall and cell rupture as a result (Misra et al., 2016a ).…”