Title

The effects of dry heat and moist heat sterilization methods on non-pathogenic strains of Escherichia coli in ground bee

Author(s)

Ahad Chattha, SVHS

School Name

Spring Valley High School

Grade Level

10th Grade

Presentation Topic

Microbiology

Presentation Type

Non-Mentored

Abstract

Escherichia coli is a Gram-negative, rod-shaped bacterium which grows in the intestinal tract of animals and humans and other environments. Pathogenic strains have been known to cause deadly diseases, such as hemorrhagic colitis and hemolytic uremic syndrome, whose symptoms include diarrhea, fever, kidney failure, and more. It is commonly found in food, especially meat products, like beef. Treatments have been made to kill it, but with using chemicals. The general population’s demand is leaning towards foods with little to no processing, which includes those treated with only heat. The two types of heat sterilization used in this study were moist heat (using water vapor) and dry heat (no water vapor). It was hypothesized that the population of E. coli on a beef patty would decrease more when it was exposed to moist heat sterilization. For experimentation, 90 beef patties were inoculated with a non-pathogenic strain of E. coli, and were divided into one of three groups. One group received moist heat sterilization through a pressure cooker, another group received dry heat sterilization through an oven, and the last group had no treatment. Agar plates were then plated and counted using a colony counter. A one-way ANOVA found a significant difference between at least one pair of means, with F(2,87)=782.06, p<0.001. A Tukey test found a significant difference between the control and the dry heat group, the control and the moist heat group, but no significant difference between the moist heat and dry heat groups.

Location

Neville 221

Start Date

4-14-2018 12:00 PM

Presentation Format

Oral and Written

COinS
 
Apr 14th, 12:00 PM

The effects of dry heat and moist heat sterilization methods on non-pathogenic strains of Escherichia coli in ground bee

Neville 221

Escherichia coli is a Gram-negative, rod-shaped bacterium which grows in the intestinal tract of animals and humans and other environments. Pathogenic strains have been known to cause deadly diseases, such as hemorrhagic colitis and hemolytic uremic syndrome, whose symptoms include diarrhea, fever, kidney failure, and more. It is commonly found in food, especially meat products, like beef. Treatments have been made to kill it, but with using chemicals. The general population’s demand is leaning towards foods with little to no processing, which includes those treated with only heat. The two types of heat sterilization used in this study were moist heat (using water vapor) and dry heat (no water vapor). It was hypothesized that the population of E. coli on a beef patty would decrease more when it was exposed to moist heat sterilization. For experimentation, 90 beef patties were inoculated with a non-pathogenic strain of E. coli, and were divided into one of three groups. One group received moist heat sterilization through a pressure cooker, another group received dry heat sterilization through an oven, and the last group had no treatment. Agar plates were then plated and counted using a colony counter. A one-way ANOVA found a significant difference between at least one pair of means, with F(2,87)=782.06, p<0.001. A Tukey test found a significant difference between the control and the dry heat group, the control and the moist heat group, but no significant difference between the moist heat and dry heat groups.