Numbers and species of motile aeromonads during the manufacture of naturally contaminated Spanish fermented sausages (longaniza and chorizo).

The prevalence of aeromonads in the initial mixes of 14 batches of chorizo and longaniza obtained from three small- and middle-sized factories was 78.5%, with counts ranging from >1.00 to 4.47 log10 CFU/g. Only 2 of 10 mixture samples prepared at a large and modern processing plant yielded these organisms, with levels below 1 log10 CFU/g. The hygienic status of factories significantly affected incidence and counts. Of 39 presumptive isolates from glutamate starch penicillin agar, 36 were confirmed as motile aeromonads and allocated to Aeromonas hydrophila (n = 24), A. veronii biovar sobria (n = 10), and A. caviae (n = 2). All of them were beta-hemolytic and capable of growing at 5 degrees C. Regardless of initial contamination, aeromonads were rapidly inactivated during the early stages of manufacture.