The evaluation of the microbial safety of fresh ready-to-eat vegetables produced by different technologies in Italy

Abstract

Aims: The study was performed to evaluate the safety of whole and RTE vegetables and to investigate the effectiveness of different preventive strategies for the quality assurance of RTE vegetables collected from three Italian production systems. Producer 1, applied a strict system in compliance with GAP‐ GMP – HACCP, Producer 2 used chlorine disinfection at a second washing step, and Producer 3 using a physical microbial stabilization. Methods: During the period 2005–2007, a total of 964 samples including whole vegetables and RTE salads, collected from three different producers in central Italy, were analysed to quantify the aerobic mesophilic count (AMC) and Escherichia coli, and for the presence of Salmonella spp, Listeria monocytogenes, E. coli O157:H7, hepatitis A virus and Norovirus (NoV). Results: None of the whole vegetable samples were positive for L. monocytogenes, E. coli O157:H7, HAV and NoV; however, a low prevalence of Salmonella was found. No pathogens were detected with cultural methods in any of the RTE vegetables analysed, only two RTE samples were positive for L. monocytogenes with PCR, but were not confirmed by the cultural method. The median values of AMC in RTE vegetables measured 24 h after packaging were statistically different among the 3 producers (5·4 × 106, 1·5 × 107 and 3·7 × 107 CFU g−1, respectively; P = 0·011). The lowest level was detected in Producer 1. Conclusion: The products that were processed applying rigorously GAP, GMP and HACCP showed a better microbiological quality than those processed with chemical or physical stabilization. Study Significance and Impact: The results of the study evidenced the efficacy of GAP, GMP and HACCP in improving microbiological quality of whole and RTE vegetables.

Detection and Quantification of <i>Listeria</i><i> </i><i>m</i><i>onocytogenes</i> in Ready-to-eat Vegetables, Frozen Vegetables and Sprouts Examined by Culture Methods and Real-time PCR

“…A low occurrence of this pathogen in minimally processed vegetables has been reported by other authors [15,16,17].…”

Afyonkarahisar’da Satışa Sunulan Tüketime Hazır Bazı Salata/Mezelerin Mikrobiyolojik Kalitesi

“…In this study, 55.1% of the RTE samples were found have TVC of >6 log cfu/g which is similar to that reported by Tessi et al [17] reporting that 74.3% of RTE samples were over contaminated with aerobic counts (>10 5 CFU/g). Likewise, De Giusti et al [19] also reported high contamination levels (10 6 -10 9 CFU/g) from 60.9-82.5% of RTE vegetables in different producers. On the contrary, Patricia and Azanza [21] .…”

“…High risk conditions during food preparation should be well explained to the operators [14] . Several studies regarding the microbiological quality of various RTE foods have been reported in Brazil [15] , in Taiwan [12,16] , in Argentina [17] , in United Arab Emirates [18] , in Italy [19] and in UK [20] .…”

“…Also, the determination of TVC should be used as a simple and inexpensive parameter to control the effectiveness of the process in the HACCP monitoring plan [19] . In this study, 55.1% of the RTE samples were found have TVC of >6 log cfu/g which is similar to that reported by Tessi et al [17] reporting that 74.3% of RTE samples were over contaminated with aerobic counts (>10 5 CFU/g).…”

Is your lunch salad safe to eat? Occurrence of bacterial pathogens and potential for pathogen growth in pre-packed ready-to-eat mixed-ingredient salads

“…Listeria monocytogenes has usually been isolated at low prevalences in salads, Salmonella has occasionally been isolated and STEC and pathogenic Y. enterocolitica have generally not been found in investigations of salads [27–30]. However, since very large quantities of leafy vegetables are consumed and most are consumed raw, even minor contamination of salads can pose a risk to public health.…”