Premium
The effect of thermal treatments on the viability and infectivity of Cryptosporidium parvum on beef surfaces
Author(s) -
Moriarty E.M.,
Duffy G.,
McEvoy J.M.,
Caccio S.,
Sheridan J.J.,
McDowell D.,
Blair I.S.
Publication year - 2005
Publication title -
journal of applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 1364-5072
DOI - 10.1111/j.1365-2672.2004.02498.x
Subject(s) - cryptosporidium parvum , infectivity , cryptosporidium , viability assay , microbiology and biotechnology , inoculation , biology , contamination , food science , chemistry , in vitro , virology , feces , biochemistry , immunology , ecology , virus
Aims: The aim of this research was to examine the effect of thermal treatments on the viability and infectivity of Cryptosporidium parvum oocysts attached to a beef surface. Methods and Results: This study examined the effects of heat treatment (60 or 75°C) on the viability of C. parvum oocysts inoculated onto the surface of beef muscle estimated by vital dye assay. The infectivity of the oocysts was assessed against monolayers of HCT‐8 cells. At 60°C viability of the oocysts decreased from 100% at T 0 to 64·2% at T 60 . At 75°C the viability of the oocysts decreased from 100% at T 0 to 53·7% at T 15 and finally to 11·2% at T 60 . Oocysts were rendered noninfective against monolayers of HCT‐8 cells following treatments of 60°C/45 s and 75°C/20 s. Conclusion: The washing of carcasses with hot water and standard thermal treatments is sufficient to kill C. parvum on beef. Significance and Impact of the Study: This study found that relatively mild heat, currently used to decontaminate and heat treat beef carcasses and to cook meat products, is capable of inactivating C. parvum .