Survival of experimentally induced Toxoplasma gondii tissue cysts in vacuum packed goat meat and dry fermented goat meat sausages

Abstract

Ingestion of raw or undercooked meat is a potential source of human toxoplasmosis. The aim of this study was to determine the viability of Toxoplasma gondii cysts in vacuum packed (VP) goat meat and in dry fermented sausages (DFS), and evaluate certain physical and chemical parameters, like water activity (aw), pH value, content of salt, dry matter and fat. A portion of muscle tissue from experimentally infected animals was used for production of VP meat with or without addition of 2.5% curing salt, and stored at 4 °C or at −20 °C. Results of bioassay showed that, samples of vacuum packed Toxoplasma positive meat without salt addition were alive after six weeks at 4 °C. Incubation at −20 °C supported the viability after 3 h, but not after 4 h. After 7 days in 2.5% of curing salt, samples of T. gondii VP goat meat were still viable, but not after 14 days at 4 °C. All the DFS samples were not positive for infective cysts which mean that, they do not pose a risk of T. gondii transmission. These data suggest that vacuum packaging increases the survival of T. gondii cysts.