Effects of dielectric barrier discharge plasma and plasma-activated water on the surface microbial diversity of fresh goji berries during storage

Abstract

The effect of plasma treatment on the bacterial and fungal microbiota on the surfaces of goji berries was studied by high-throughput sequencing at 20 °C. The treatment voltage of dielectric barrier discharge (DBD) plasma was 80 kV, and the exposure time was 60 s. The treatment method of plasma-activated water (PAW) is soaking for 20 min. On the fifth day of storage, the total number of fungal colonies on the surfaces of goji berries treated with DBD plasma and PAW decreased by 1.02 and 0.994 log10CFU/g, respectively, and the total number of bacterial colonies decreased by 0.69 and 0.88 log10CFU/g, respectively compared with that in untreated goji berries (CK). Comparative analysis showed that the relative abundance of Cladosporium, Filobasidium, Aureobasidium, and Rhizopus in the DBD and PAW groups decreased after storage. This effect may reduce the risk of postharvest deterioration and pathogenic contamination of goji berries.