***PLEASE HELP-milk microbiology project

Jim WIck alpha01 at execpc.com
Wed Mar 26 08:53:09 EST 1997


My daughter did a similar study for her 8th grade science fair 
project. What she found out was that bacterial counts when ballistic 
when milk was left out at room temperature for two night. The 
experiment was set up to leave a tube of milk out on the kitchen 
counter overnight and then to return it to the refrigerator each 
morning. There was a dramatic difference between one and two night 
out on at room temperature. 

She also tested unpasturized vs pasturized milk. As expected the 
pasturized sample contained very few bacterial coloines when properly 
stored, while the unpasturized has 20-50,000 colonies per ml. By 
comparison, the sample left out two night were to numerous to count 
by our test, but we estimated many millions of colonies per ml.

I hope this info is helpful.

Jim Wick

In article <19970325160000.LAA19845 at ladder01.news.aol.com>, 
paulparty at aol.com says...
>
>I am doing a project entitled:
>'Investigating how different milk types (skimmed/whole and
>UHT/Pasteurized) and days milk is left at room temperature unexposed,
>affects the bacterial content'
>
>I am measuring bacterial content by counting colonies on incubated 
milk
>agar plates and also carrying out titrations against sodium hydroxide 
in
>order to measure lactic acid content.
>
>I would be very grateful if anyone could provide any relevant 
background
>information about milk microbiology information and what results I 
should
>expect from each of the different milk types and why.
>
>Thanks very much.
>S.Paul
>




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