Combination of organic acids and low-dose gamma irradiation as antimicrobial treatment to inactivate Shiga toxin-producing Escherichia coli inoculated in beef trimmings: Lack of benefits in relation to single treatments

CAP M.; CELESTE CINGOLANI; CARLA LIRES; MARINA MOZGOVOJ1; TRINIDAD SOTERAS; ADRIANA SUCARI; JIMENA GENTILUOMO; ADRIANA DESCALZO; GABRIELA GRIGIONI; MARCELO SIGNORINII; CELINA HORAK; SERGIO VAUDAGNA; GERARDO LEOTTA

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2020

1932-6203

The aim of this study was to assess the efficacy of lactic acid (LA), caprylic acid (CA), high-(HDI) and low- (LDI) dose gamma irradiation and LDI combined with LA or CA on the inactivationof a pool of Shiga toxin-producing Escherichia coli (STEC) strains inoculated on beeftrimmings. The three most efficacious treatments were selected to study their effect on meatquality parameters and sensory attributes. The inoculum included five native STEC serogroups(O26, O103, O111, O145 and O157). The treatments applied were 0.5% LA,0.04% CA, 0.5 kGy LDI, 2 kGy HDI, LDI+LA and LDI+CA. Beef trimmings were divided intotwo groups; one was inoculated with high (7 log CFU/g) and the other with low (1 log CFU/g)level of inoculum. Efficacy was assessed by estimating log reduction and reduction of stxandeae-positive samples after enrichment, respectively. Results showed that treatmentswith organic acids alone were not effective in reducing STEC populations. For high inoculumsamples, the most effective treatment was HDI followed by LDI+LA and LDI alone or combinedwith CA. For low inoculum samples, the most effective treatment was HDI followed byLDI alone or combined with organic acids. Concerning meat quality parameters and sensoryattributes, irradiation treatments (LDI and HDI) caused minimal changes, while LDI+LAmodified them significantly compared with the control. Therefore, based on our results, nobenefits were observed after combining organic acids with gamma irradiation.