Analysis of Cooking Temperatures on Escherichia coli Bacteria

Laaron Hozak


Department of Biology and Chemistry

Lake Superior State University

Sault Ste. Marie, MI



Abstract



	Escherichia coli bacteria are gram negative rods that are
found in the intestines of some cattle and can be ground into
beef during improper handling.  Some H strains of this bacteria
cause a bloody-watery-mucous filled diarrhea that can be very
deadly to the young and elderly.  Federal guidelines suggest
cooking ground beef to a temperature of 68 degrees Celsius to
kill any E. coil that may be present.  E. coil tainted broths
were heated to four different temperatures: control (no heat), 60
degrees Celsius, 68 degrees Celsius and 77 degrees Celsius.  In
all, ten trials for each group were done.  For each trial a pour
plate was made and the number of bacterial colonies counted.  A
one factor ANOVA test was done at .05 level of confidence to test
if there was a significant difference between the mean number of
bacterial colonies counted for each group.  The ANOVA test did
show a significant difference between the group means.  A Tukey's
Multiple comparison test was then performed to determine which
groups differed significantly.  The comparison tests showed no
significant difference between the means for the control, 60
degree or the 77 degree groups.  It did however, show a
significant difference between the mean of the 77 degree group
when compared to any of the other three.


Selected References



Bryant, A. "Foodmaker Halts Expansion Plans."  The New York
	Times.  Monday February 15, 1993.  Section D,  Financial
	Desk  p.1.

Greenburg, R. (Producer) .  "Always Well Done."  ABC News
	20/20.  September 22, 1995.  ABC.