Food Protection Trends - November/December 2017 - 407

the same hypothesis as Kotula et al. (12), Scanga et al.
(16) reported that as the fat content of beef trimmings
increased, the aerobic counts also increased, with 30%
fat trimmings having the highest aerobic bacteria counts,
compared with 10, 20, or 50%; however, there were no
significant differences in total coliform, generic E. coli, or
Staphylococcus aureus counts across fat percentages. When
the samples were collected via a combo-bin purge, there
were no significant differences among microbial indicator
counts across any values for fat content of the samples.
The concentration of background organisms in trim
may vary because of the effectiveness of sanitary hide
removal, processing interventions, and adequate cold
chain management (4). In this study, production shift -
morning, midday, or evening - did not significantly affect
the load and distribution of aerobic counts (Fig. 1). This
demonstrates highly consistent hygienic practices during
production, and/or may indicate that the microbiological
quality of the incoming carcasses used for fabrication is
consistent. Although non-significant, there was a slight
tendency for numbers of aerobic bacteria to be lower during
the midday shift. There was no clear tendency for the
distribution of CC and EC, and given that all counts were
under the limit of quantification, it would be impossible to
make inferences about those values.
Finally, we attempted to determine the linear relationship
between the visually estimated surface fat content (min-

imum and maximum values of the range for chuck, heel,
and shank, and a set value of 70% for sparse lean) and the
concentration of aerobic plate counts. The correlation coefficients ranged from 0.044 to 0.057, indicating that surface
fat content may be an extremely poor predictor of the load
of aerobic bacteria on beef trimmings, if a linear relationship
between the two variables is assumed.
CONCLUSIONS
The carcass anatomical location does not significantly
affect the surface microbiological profiles of beef trimmings
destined for ground beef production, as indicated by the
load of aerobic bacteria, coliforms, and generic E. coli.
The overall differences observed in this study, even when
statistically significant, are too small to be likely to have an
impact on food safety or quality. Not surprisingly, surface
fat content (used as a proxy for carcass location) was found
to be an extremely poor predictor of the concentration of
aerobic bacteria on beef trimmings. In establishments with
adequate and strict sanitation, cold chain, and fabrication
practices in place, and with adequate standards of the
hygienic status of incoming carcasses, the location of the
trimmings, even with varying surface fat contents, does
not influence their microbiological status and should not
negatively impact the safety or quality of the resulting
ground beef and ground beef products.

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http://www.meatscience.org/docs/default-source/publications-resources/white-papers/the-role-of-microbiological-testing-in-beef-food-safety-programs.pdf?sfvrsn=0 http://www.meatscience.org/docs/default-source/publications-resources/white-papers/the-role-of-microbiological-testing-in-beef-food-safety-programs.pdf?sfvrsn=0 http://www.meatscience.org/docs/default-source/publications-resources/white-papers/the-role-of-microbiological-testing-in-beef-food-safety-programs.pdf?sfvrsn=0 http://www.meatscience.org/docs/default-source/publications-resources/white-papers/the-role-of-microbiological-testing-in-beef-food-safety-programs.pdf?sfvrsn=0 http://www.meatscience.org/docs/default-source/publications-resources/white-papers/the-role-of-microbiological-testing-in-beef-food-safety-programs.pdf?sfvrsn=0 http://www.gftc.ca/knowledge-library/file.aspx?id=360d45f1- 74c8-4085-9595-11ba90d7c71e http://www.gftc.ca/knowledge-library/file.aspx?id=360d45f1- 74c8-4085-9595-11ba90d7c71e http://www.gftc.ca/knowledge-library/file.aspx?id=360d45f1- 74c8-4085-9595-11ba90d7c71e

Table of Contents for the Digital Edition of Food Protection Trends - November/December 2017