Day 11:  Back into the lab with Adam.  Adam showed me how to make a fermentation medium.  For out test and instruction run.  We made a medium which has two parts to be combined in a bioreactor.  The first half was 750 Ml of water with 10g of Peptone a protein and 5g of yeast extract.  The second part was 100g of Dextrose in 200 Ml of water.  We used a machine called a Milli-Q. This machine makes pure water by filtration. It is similar to double distilled water.  I got to use one of those cool magnetic mixers as you can see in the second picture where part one is mixing.  In the next two pictures you see me making part two.  Adam and I each made one with me basically following his lead and learning by example.  On the left I am measuring out the Dextrose and in the second I am slowing adding the dextrose to water while it is set on a mixer.  Adam told me this allows the dextrose to dissolve in the water more evenly.  If you dumped it in it would tend to clump.

After these two parts are sterilized in the autoclave, we take them out and begin to prepare the fermentation vessel in the bioreactor.  In the picture on the left adam and I are setting up the fermentation vessels with part one of our medium in it.  On the right is the dextrose dissolved in water on the magnetic mixer.  These parts are put in the autoclave for about an hour.  I learned to run the bioreactor which you can see in my previous post from yesterday.  Part of learning to run the bioreactor was to calibrate a ph meter and using a touch screen to set up the test parameters.  Next we add the dextrose mixture to the Peptone and yeast extract mixture.  When this combination is finished we set the control temperatures and the ph parameter we want for the test.  My bioreactor was set to run at 40C and Adam's was set at 30C.  In the bottom left picture you can see adam weighing out the yeast on a very accurate scale.  This measures out to 4 decimal places.  We pitched the yeast (inoculated as Adam called it), got this all set up and pushed go.  At different stages of this process we used a spectrophotometer to measure the cell density of the fermentation mixture.  This is determined by how much light passes through the mixture in the device.  Tomorrow we will start seeing the results of the fermentation.

The last image on the right here is the final  assembly of the Hammer mill with the paint job completed.  Junior got this together in my absence.  I will try and find a before picture so you can truly appreciate the effort Junior put into this.