Use of cold atmospheric plasma to preserve the quality of white shrimp (litopenaeus vannamei)

Abstract

The enzymatic oxidation process that causes black spots on shrimp, named melanosis, leads to spoilage and economic losses. Therefore, there is an urgent need for strategies to reduce melanosis in the food industry. Cold plasma is an emerging nonthermal food processing technology. This work explores a novel application of cold plasma for the preservation of shrimp quality. This study aimed to evaluate the effects of cold plasma on the quality attributes of Pacific white shrimp (Litopenaeus vannamei). The shrimp samples were divided in two groups: the control group and the plasma group. Samples were exposed to nonthermal plasma for 10 min at a frequency of 500 Hz. Microbiological assays, including total counts of mesophilic and psychrotrophic bacteria, Staphylococcus spp., and Salmonella sp., were performed along with investigations of physicochemical parameters, such as pH, color, water-holding capacity, cooking loss, and shear force. In addition, sensory (quality index method) tests were conducted. The plasma group exhibited a shelf life of 14.07 days, while the control group exhibited a shelf life of 9.78 days. The experimental protocol used in this study was not enough to obtain significant reduction in the bacterial load. However, treatment with the cold plasma contributed to improving the physicochemical properties during storage.