Transcript Cutting Boards: Is That Surface Really Clean?

Cutting Boards: Is That Surface
Really Clean?
Background Information
• Escherichia coli(E.coli)
• Escherichia coli is a common
bacterium found in the human
and animal intestinal tract.
• It aids digestion, fights
possible infection in the
intestinal tract, and produces
small amounts of vitamins B12
and K
• E coli food poisoning occurs
when, usually raw meat, or
contaminated subjects are
taken in by a person.
• The result are abdominal pain,
diarrhea, vomiting and fever.
• Tests on bamboo cutting
boards
• Cook’s Illustrated magazine
found that in an independent
lab test, bamboo cutting
boards did have some natural
bacteria-killing properties
when compared to composite,
wood and plastic boards.
• Greenearthbamboo.com
claims that bamboo is
antimicrobial and that it is
disliked by pests and
pathogens; therefore making it
antibacterial.
Question
Are bamboo cutting boards naturally
antibacterial when exposed to raw chicken
drippings?
Hypothesis
If fewer bacteria are found on the bamboo
cutting board when compared to plastic and
wood cutting boards, then bamboo is
naturally antibacterial.
• Independent Variable: type of cutting board
used.
• Dependant Variable: How much extracted
bacteria is grown from the surface of the
cutting board.
• Constants: The even spreading of chicken
drippings, sterile swabs, Easy Gel
coliscans, Petri dishes, and temperature at
which the dishes were held in incubator.
Procedure
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Clean all surface areas.
Wash all bamboo, plastic and wood cutting boards with a 10% bleach solution(100mL
bleach; 900mL water).
Once boards are dry, take sterilized swab, dip it in the Easy Gel Coliscan agar and
remove.
Swab an area 15cm long and 3cm wide back and forth three times on each board.
Swirl in coliscan bottle and pour into Petri dish.
Take raw chicken drippings and evenly spread it over boards.
Let sit to dry for 15 minutes and then repeat the swab technique.
Wash boards with tap water and dry. Again, take three samples from each board using
the sterile swabs, coliscans, and Petri dishes.
Wash boards with 5g of PalmOlive dish soap and 1L of tap water.
Allow to dry and take samples again by using a sterile swab, caliscan and Petri dish.
Clean all boards again in 10% bleach solution(100mL bleach; 900mL water) and dispose
of used materials.
Place Petri dishes in incubator for three days at a temperature of 37⁰C.
Then remove and count the bacteria colonies. Record results.
50
45
40
Coliscan Count
35
30
White
25
Pink
20
Purple
15
10
5
0
Bamboo
Wood
Averaged Contaminated Results
Plastic
0.7
0.6
0.5
Coliscan Count
White
0.4
Pink
0.3
Purple
0.2
0.1
0
Bamboo
Wood
Averaged Results When Washed With Water
Plastic
Variables
• Only one packet of chicken was tested.
• All three boards were new.
• When contaminated, they were exposed to
open air.
Conclusion
• Both the wood and plastic cutting boards retained more bacteria than the
bamboo.
• The results of this experiment suggest that while wood and plastic cutting
boards retained bacteria, the bamboo cutting board did not; therefore,
implying that it is naturally antibacterial.
• Used cutting boards should be tested in the same way to more determine
the natural antibacterial qualities of bamboo cutting boards and clarify
which is safer to use in the kitchen.
• In the experiment, it was observed that water alone was enough to rid the
cutting boards of most bacteria. Soap and water combined eliminated the
bacteria completely, suggesting that simple cleaning was an effective way
to dispel any bacteria.
• The hypothesis was supported in the sense that the wood and plastic
boards contained a considerable amount of bacterial whereas the bamboo
did not. This lack of bacteria on the bamboo supported the hypothesis,
rendering it naturally antibacterial.
Bibliography
• "E. Coli Food Poisoning." Infoplease. Family Education
Network, 2005. Web. 9 Feb.
2011.<http://www.infoplease.com/ce6/sci/A0858027.h
tml>.
• "Escherichia Coli." Infoplease. Family Education
Network, 2005. Web. 9 Feb. 2011.
<http://www.infoplease.com/ce6/sci/A0817668.html>.
• "Cutting Boards Reviews and Research." Consumer
Search. New York Times Co, 1
Jan. 2008. Web. 9 Feb. 2011.
<http://www.consumersearch.com/
cutting-boards/reviews>.