DISINFECTION OF MARKETABLE EGGS BY PLASMA-CHEMICALLY ACTIVATED AQUEOUS SOLUTIONS

Abstract

Microbiological purity of raw materials and finished products is one of the most important factors of food safety. The acceptable level of microbiological contamination is provided by a set of sanitary and hygienic techniques in the course of manufacturing, selling, and consuming food products. It has been suggested that eggs should be disinfected by treating them with plasma-chemically activated aqueous solutions in order to reduce microbial contamination of the egg surfaces and remove salmonella from them. The surface of eggs is disinfected with aqueous solutions activated by non-equilibrium contact plasma with the different time of activation of these solutions. Plasma-chemically activated aqueous solutions act as high-quality disinfectants. They contain an active substance (hydrogen peroxide) with the concentration of 100 to 700 mg/l, and have pronounced antiseptic properties. The studies have revealed that with the use of plasma-chemically activated aqueous solutions as a disinfectant, the number of bacteria and fungi on the eggshell is significantly reduced. For example, E. coli and S. Enteritidis were not found in samples at the peroxide concentration as high as 100 mg/l, while the total bacterial contamination and pathogenic microflora under study (E. сoli, Asp. fumigatus, S. Enteritidis) were absent at 300 mg/l concentration of peroxides. Besides, our research included bacteriological studies of marketable eggs in storage. Thus, plasma-chemically activated aqueous solutions with the peroxide concentration 300 mg/l, besides destroying the pathogenic microflora completely (as evidenced by the total absence of QMAFAnM, CFU/cm3, S. enteritidis, E. coli, Asp. fumigatus in the studied samples), had a long-term disinfection effect: no pathogenic microflora appeared on the surface of the eggs within a month. This will allow extending the shelf life of marketable eggs. The studies of microbiological parameters of the dirty eggshells treated with plasma-chemically activated aqueous solutions have shown that the 400 mg/l concentration of peroxides allows getting rid of coliform bacteria, staphylococci, salmonella, spore-forming microflora, which makes a product saleable. The outward appearance of raw materials improves as well, which indicates a wide range of applications of the proposed technology of egg surface disinfection.