Cold plasma treatment for decontamination of pesticide residues and preservation of spinach leaves

Abstract

Spinach (Spinacia oleracea L.) is a nutritious, perishable, leafy vegetable with a short shelf life and high post-harvest losses. This study investigated the efficacy of cold plasma treatments to reduce the microbial load from the spinach leaf and prolong its shelf life. A comparative analysis was performed using techniques like ozone and chlorine wash [Acidified sodium chlorite (ASC)] for analysing its efficacy. The study also evaluated the effectiveness of various decontamination treatments in removing pesticide residues. Treatment with cold plasma reduced the physiological weight loss, decay rate, microbial count, and enzyme activity and retained the color. The spinach's total phenolic content (TPC) was elevated following cold plasma treatments (>50 % higher than control at the end of cold storage). Organophosphate residues from the spinach surface were reduced (∼90 % reduction in chlorpyrifos and malathion) after cold plasma treatment. The results of study indicated that cold plasma is a promising alternative to the existing hypochlorite wash. This innovative technique has a promising future in the fresh produce industry to prevent post-harvest losses through enzyme inactivation, microbial load reduction, and pesticide decontamination.