September 11, 2020

Less than thoroughly cooked (LTTC) burgers reviewed to ensure safety



Burgers served rare were reviewed to ensure they are as safe as those thoroughly cooked.


The United Kingdom's Food Standards Agency (FSA) was concerned about the increased risk of E. coli O157 infections as sales and consumption of burgers served LTTC and pink in the middle became a growing trend.


The FSA believes that burgers served as LTTC should have the same level of protection as a thoroughly cooked beef, which is, a 6 log reduction in microbial load. However, it is unlikely this will be achieved solely at the catering level. Safe production of LTTC burgers to reduce microbiological risks is likely dependent on controls and interventions at beef processing facilities in the upper supply chain.

Food firms serving LTTC burgers must have documented and validated evidence of procedures in the supply chain that can achieve at least a 4 log reduction before the burger is served to the consumer.


According to the review, apart from E-beam irradiation, no single intervention can realistically deliver 4 log reduction of microbiota on carcasses or beef cuts.


Consumer protection


"The integrated and coordinated use of multiple interventions in the ground beef production chain may be able to reduce microbial loads sufficiently to offer the same level of protection to consumers from burgers, which are produced with these interventions and are served LTTC as that of thoroughly cooked burgers originating from the conventional ground beef production chain," according to the review by Dragan Antic at the University of Liverpool (UK).


More than 300 articles were used for data extraction and reporting. The work covered a range of GHP-based and hazard-based interventions for cattle received in abattoir, including finished product packaging and storage.

The review looked at the effectiveness of each intervention in reducing indicator bacteria such as aerobic colony counts, Enterobacteriaceae, total coliform and generic E. coli counts, and foodborne pathogens, primarily E. coli O157 and other Shiga toxin producing E. coli and Salmonella.

European abattoirs are only permitted the use of potable water, thermal treatment with hot water and steam pasteurisation, and lactic acid for beef carcass washing.


Stage and type of measures

Multiple uses of interventions featuring knife trimming, steam vacuuming, pasteurisation treatments and organic acid washes had the biggest impact on microbial reduction on beef carcasses, more than any of them applied alone.


Pre-slaughter beef interventions include good hygiene practices such as lairage cleaning, proper cattle handling to prevent cross-contamination and cleanliness assessment.

Post-slaughter interventions included good hygiene practices during carcass fabrication to prevent and minimise carcass cross-contamination post-chill. Hot water or chemical substances have shown good reduction effects but these treatments can only be used if optimised to retain the acceptable sensory quality of final products.


Modified atmosphere packaging (MAP) and vacuum packaging are useful to extend the shelf life of trim and ground beef. However, they had a very limited impact on E. coli O157:H7.


According to the report, new technologies for beef, such as electron beam, gamma and UV light irradiation, high-pressure processing, cold atmospheric plasma and bacteriophage treatments, merit further investigation but commercial uptake will depend on consumer acceptance.


- Food Safety News