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Aims Plant-based alternatives to meat and dairy products have become increasingly popular in the UK. Despite a public perception that they have a relatively low microbiological risk, outbreaks of illness have been linked with these foods. This study aimed to assess the microbiological safety and quality of vegan alternatives to dairy and meat products available in England. Methods and results Samples were collected between September 2022 and March 2023 from retail, production, and catering premises, and tested for a range of bacterial pathogens and hygiene indicators using standard procedures. A total of 937 samples were tested, of which 92% were of a satisfactory microbiological quality, 3% were borderline, and 5% were unsatisfactory. Those interpreted as unsatisfactory were due to elevated counts of Enterobacteriaceae and Escherichia coli (indicators of poor hygiene) rather than pathogenic microorganisms. Listeria monocytogenes was present in five samples of tofu, all from the same producer (all at counts of <100 CFU g–1), while other Listeria species were detected at counts of <20 CFU g–1 in two burgers and two 'vegan chicken' products. The majority of samples did not have pH and water activity values that would significantly contribute to preventing microbial growth: 62.4% had pH > 5.0 and 82.4% had A w > 0.94. Conclusions The majority of vegan products examined were of a satisfactory quality, but results demonstrate that microbiological control must be maintained using appropriate processing and storage temperatures, and application of a safe length of shelf life. [ABSTRACT FROM AUTHOR]

Aim To investigate the possible contamination of raw flour and raw flour-based products, such as pancake/batter mixes, with Salmonella , generic Escherichia coli , and Shiga-toxin-producing E. coli (STEC). Samples included flours available for sale in the UK over a period of four months (January to April 2020). The Bread and Flour regulations, 1998 state the permitted ingredients in flour and bread but it does not specify the regular monitoring of the microbiological quality of flour and flour-based products. Methods and results Samples of raw flour were collected by local authority sampling officers in accordance with current guidance on microbiological food sampling then transported to the laboratory for examination. Microbiological testing was performed to detect Salmonella spp. generic E. coli , and STEC characterized for the presence of STEC virulence genes: stx 1, stx 2, and subtypes, eae, ipah, aggR, lt, sth , and stp , using molecular methods Polymerase Chain Reaction (PCR). Of the 882 flours sampled, the incidence of Salmonella was 0.1% (a single positive sample that contained multiple ingredients such as flour, dried egg, and dried milk, milled in the UK), and 68 samples (7.7%) contained generic E. coli at a level of >20 CFU/g. Molecular characterization of flour samples revealed the presence of the Shiga-toxin (stx) gene in 10 samples (5 imported and 5 from the UK) (1.1%), from which STEC was isolated from 7 samples (0.8%). Salmonella and STEC isolates were sequenced to provide further characterization of genotypes and to compare to sequences of human clinical isolates held in the UKHSA archive. Using our interpretive criteria based on genetic similarity, none of the STEC flour isolates correlated with previously observed human cases, while the singular Salmonella serotype Newport isolate from the mixed ingredient product was similar to a human case in 2019, from the UK, of S. Newport. Although there have been no reported human cases of STEC matching the isolates from these flour samples, some of the same serotypes and stx subtypes detected are known to have caused illness in other contexts. Conclusion Results indicate that while the incidence was low, there is a potential for the presence of Salmonella and STEC in flour, and a genetic link was demonstrated between a Salmonella isolate from a flour-based product and a human case of salmonellosis. [ABSTRACT FROM AUTHOR]

Aim Frozen, breaded chicken products have been implicated in Salmonella outbreaks, and may be incorrectly perceived as ready-to-eat, leading to mishandling or undercooking by consumers. This study aimed to assess the prevalence of Salmonella and antimicrobial resistant (AMR) Escherichia coli in these products. Methods and results Samples of frozen, raw, or partly cooked, coated chicken products were collected between April and July 2021 from retailers in the UK and tested for Salmonella spp. generic E. coli , extended spectrum beta-lactamase-producing, colistin-resistant, and carbapenem-resistant E. coli. One isolate of each bacterial type from each sample was selected for minimum inhibitory concentration determination for a range of antimicrobials. Salmonella was detected in 5 of 310 (1.6%) samples, identified as Salmonella Infantis in three samples and Salm. Java in two. One Salm. Infantis isolate was multidrug resistant, while the other Salmonella isolates were each resistant to at least one class of antimicrobials. Generic E. coli were detected in 113 samples (36.4%), with multidrug resistance being demonstrated in 20.0% of these. Escherichia coli with the ESBL phenotype were detected in 15 (4.8%) of samples and the AmpC phenotype in 2 (0.6%). A colistin-resistant E. coli was isolated from one sample; this possessed the mcr-1 gene. No carbapenem-resistant E. coli were detected. The five Salmonella -positive samples from this study, together with 20 Salmonella -positive products from an earlier study in 2020/2021, were cooked according to the manufacturers' instructions. Following cooking, Salmonella was not detected in any samples. Conclusions This survey demonstrates continued contamination of frozen, coated chicken products with Salmonella , and provides data on the prevalence of AMR in these products. [ABSTRACT FROM AUTHOR]