Testing for Bacteria
I have to do a science fair project. What I need to
compare the relative bacterial levels in milk samples with different
expiration dates. What can I use to test the bacteria? Please help!
You want to see if there are bacteria present in milk
of different expiration dates, and if so, what they do
to the milk. So buy milk of different dates. You could
test what effect storage temperature has on bacterial
growth in milk. Use those different milk samples in
their original package (don't open it!) and keep them
at 37 degrees C, at room temperature, and in the
fridge (measure how cold that is) for say 48 hrs.Then
open the bottle or pack and see what happened to the
milk. Do you see differences? Can you explain them?
If you open the milk before the experiment you may get
bacteria into the milk that otherwise would not have
been there. The experiment with the closed bottles
will tell you what is better, storage of milk at room
temperature, warm, or cold.
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Update: June 2012