The prevalence and number of Salmonella in sausages and their destruction by frying, grilling or barbecuing

Abstract

Aims: To determine the prevalence and number of Salmonella and Campylobacter in sausages and to evaluate their destruction during cooking. Methods and Results: One hundred and sixty-two packs of uncooked economy or catering sausages, comprising 53 packs of frozen and 109 of chilled sausages, were purchased in Devon between March and July 2000. All were tested for the presence of Salmonella and 51 packs of chilled sausages were also examined for the presence of Campylobacter spp. To investigate the heat tolerance of Salmonella enterica serovar Typhimurium DT104 in sausage-meat, chilled, handmade and frozen sausages were inoculated with approx. 1AE5 · 10 4 bacterial cells per sausage (300 cfu g)1 ) and then cooked by frying, grilling or barbecuing. The levels of creatinine kinase, lactate dehydrogenase and alkaline phosphatase in uncooked and cooked sausages were measured to evaluate their potential as indicators of adequate cooking and, therefore, pathogen elimination. Salmonella were detected in 7AE5% of frozen and 9AE1% of the chilled sausages (8AE6% overall) but Campylobacter spp. were not isolated. After cooking, a visual assessment suggested that all of the sausages were thoroughly cooked. Despite this, barbecuing and frying sometimes allowed Salmonella cells to survive and the temperature profiles during cooking indicated that the lethal range was sometimes not reached. The enzyme levels tested were not reliable indicators of the inactivation of bacterial pathogens because Salmonella were sometimes isolated from sausages with low values of all three enzymes. Conclusions: Salmonella spp. are present in a significant proportion of sausages and are not always killed during the cooking process. Significance and Impact of the Study: These findings have clear implications for public health.

Evaluation of the BAX® system for the detection of Salmonella spp. in naturally contaminated chicken meat

“…According to Mattick et al (2002), one of the main problems in the isolation of Salmonella in foods is the small number of these bacteria considering the rate of bacterial contamination. According to Bennett et al (1998), the BAX® system always produced a positive result when the cell count of Salmonella spp.…”

Microbiological quality of Merguez in some retailing meat shops in the region of MSila (Algeria)

“…Our results were similar to those obtained by Seydi and Sylla (1996) in Dakar, but were clearly inferior to those of Elhag et al (2014) in Khartoum who revealed that 97.5% of the studied sausage samples were contaminated by these bacteria. Many studies showed than the Salmonella can be isolated from various types of sausages (Abrahim et al, 1998;Mattick et al, 2002;Özbey et al, 2007). The high incidence of these bacteria could be due to the faeces contamination of the chopped meat used for the production of pork-butchery, contaminated water, the environment and bad hygiene of workers (Reid et al, 2002).…”

Impact of Inoculum Preparation and Storage Conditions on the Response of Escherichia coli O157:H7 Populations to Undercooking and Simulated Exposure to Gastric Fluid

“…The four-strain composite culture was used to inoculate various substrates in order to prepare the inocula under representative environmental conditions (inoculum origin). The control inoculum (TSB) was obtained by inoculating (5 log CFU/ml) TSB-G with the composite E. coli O157:H7 culture (1 ml), and, after overnight incubation at 35°C, the resulting cell suspension was diluted (1,000-fold) in sterilized maximum-recovery diluent (MRD; 1.0 g peptone [Difco] and 8.5 g sodium chloride [Fisher Scientific, Fair Lawn, NJ] in 1 liter distilled water) (18).…”