can inhibit E. coli growth in ground beef, says US study
By Jane Byrne, 05-Dec-2008
Source of Article: http://www.foodproductiondaily.com/Quality-Safety/Cranberry-can-inhibit-E.-coli-growth-in-ground-beef-says-US-study
addition of cranberry concentrate to ground beef may serve as an supplementary hurdle to control potential E. coli
O157:H7 outbreaks associated with ground beef, claims a new US study.
Researchers at the
University of Maine examined the potential for cranberry
concentrate (CC) to be used as a natural food preservative by examining its antimicrobial
effect on the growth of Escherichia coli O157:H7 inoculated in ground beef
as well as its organoleptical effect on beef
The findings of the
research, which was published in the journal Food Microbiology, indicated
that cranberry concentrate at the tested concentrations did not cause
significant negative impact on the flavour, taste or colour of burgers and
also possessed antimicrobial effects.
The application of
cranberry concentrate at low concentrations in ground beef as an additional
hurdle to prevent possible E. coli O157:H7 contamination has not been
previously reported, claim the authors.
Ground beef is a
potentially hazardous food which can harbour pathogenic microorganisms and
permit their growth or the production of toxins if temperature and time are
not controlled, claim the authors of the study.
E. coli O157:H7 can survive
in healthy cow guts and may contaminate beef when cows are slaughtered.
In the US this year,
millions of pounds of raw ground beef were recalled because of E. coli
O157:H7 contamination, and the researchers stress
that effective methods to prevent and eliminate such contaminations in ground
beef are as such essential for the food industry and consumers.
Consumers today tend
to choose food products that are natural, safe, and with multi-health
benefits; burgers with cranberry concentrate, according to the researchers,
may be a product that can meet their requirements.
The article reports
that American cranberries (Vaccinium macrocarpon) contain many bioactive compounds that
have antioxidant, anti-mutagenic, antihypercholesterolemic
and other beneficial health properties.
However, the authors
said that they included sensory evaluation as part of their research to
determine if consumers would accept the organoleptical
properties of ground beef inoculated with cranberry concentrate.
Inoculated ground beef
was added with CC and stored at 4°C for five days, said the authors.
(2.5 per cent, 5 per cent, and 7.5 per cent w/w) reduced E. coli
O157:H7 population by 0.4 log, 0.7 log, and 2.4 log, respectively, when
compared to the control on day five, claims the team.
They added that the
inhibition effect of cranberry concentrate increased with time and
In addition, 50 panelists evaluated the burgers supplemented with CC, and
no differences in appearance, flavour, and taste were found among burgers
with 0 per cent, 2.5 per cent, and 5 per cent CC.
Published online ahead of print
Title: Application of cranberry concentrate (Vaccinium
macrocarpon) to control Escherichia coli O157:H7 in
ground beef and its antimicrobial mechanism related to the downregulated slp, hdeA and cfa
Authors: V. C.H. Wu, X Qiu, B. G. de los Reyes,
C.S. Lin, Y. Pan