title: Isolation and characterization of Shiga toxin-producing Escherichia coli from precooked sausages (morcillas).
abstract: The aim of the study was to establish the microbiological quality of morcillas, typical Argentine sausages, and to investigate the presence of Shiga toxin-producing Escherichia coli (STEC). Between October 2001 and October 2002, a total of 100 morcilla samples were analysed. Several samples showed high levels of total aerobic mesophilic bacteria counts, molds and yeasts. The samples analysed contained Enterobacteriaceae (100%) and fecal coliforms (81%), indicating inadequate application of the thermal treatment and deficient hygiene conditions during the elaboration of the product. STEC strains were isolated from three out of 100 (3%) morcilla samples. Two strains (2%) were characterized as E. coli O157:H7 stx2+stx2vh-a/eae/EHEC-hlyA and one strain (1%), as E. coli O26:H11 stx1/eae/EHEC-hlyA. Considering both the high microbial count in all tested samples and the presence of STEC strains in three of them, morcillas should be considered a food unsafe to consume when inadequately cooked.
authors.affiliation: Center for Research and Development of Food Cryotechnology (CIDCA), National University of La Plata, Faculty of Sciences, Calle 47 y 116, (1900) La Plata, Argentina. jmoteiza@cidca.org.ar
authors.forename: Juan M
authors.initials: JM
authors.lastname: Oteiza
authors.forename: Isabel
authors.initials: I
authors.lastname: Chinen
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Miliwebsky
authors.forename: Marta
authors.initials: M
authors.lastname: Rivas
mesh_terms: D000818:Animals; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004755:Enterobacteriaceae / Q000302:isolation & purification; D004926:Escherichia coli / Q000302:isolation & purification*; D019453:Escherichia coli O157 / Q000302:isolation & purification*; D005506:Food Contamination / Q000032:analysis*; D005525:Food-Processing Industry / Q000379:methods / Q000592:standards*; D006801:Humans; D006920:Hygiene; D008461:Meat Products / Q000382:microbiology* / Q000592:standards; D022603:Shiga Toxins / Q000096:biosynthesis*; D013552:Swine
chemical_list: D022603:Shiga Toxins