So Long Sourdough Starters!

The Beginning of The End

The last update on my starters consisted of observations from February 8th to February 18th.  There was very little progress to share during that time. On February 19th, however, my original control starter began to rise. It was rising pretty consistently for a couple of days, but then it seemed to show less bubbles and growth each day. Its health declined rapidly which led me to dispose of all four starters since I did not have any viable samples to submit for sequencing. Below I have attached images from February 19th and 20th, the days my original control starter showed the most growth. 



The two images above are both of my original starters on February 19th, taken around 9:30 am. At this point, I had been feeding my original starters and newer starters differently. My original starters were being refreshed each day by having 1 TBSP of old mixture taken out and then adding 1 TBSP of water and 4.5 TSP of flour. For the newer starters, I was removing 1 TBSP of the old mixture then adding 1 TBSP of water and 5 TSP of flour. The original starters already had a slightly thicker consistency than my newer starters, and adding a little more flour each day seemed to be creating the texture or consistency in both starters that was necessary for them to begin rising. The newer starters were also thickening but never really showed any progress or bubbles.   



This is an image of the surfaces of my original starters
also taken around 9:30 am on February 19th. This was
the day of my original starters' 22nd feeding. 






The image to the left was taken around 9:35 am on February 19th of the original control starter. After observing the appearance of the starters, I began to stir them to see if there had been any changes in the aroma or consistency. I was surprised to find that there was not an unpleasant smell coming from the control starter since it was now rising. However, the consistency seemed to be thicker and almost fluffy. 





This image was taken of the original control starter on the same date, around the same time before I stirred it. I could tell from the surface of this starter that the consistency was going to be different from that of the experimental starter. 











This image was taken of the surface of the experimental starter on the same day, at the same time. The surface was very smooth, and there were no bubbles visible through the sides of the cups. Once I stirred this starter, I was able to determine that there had been no significant changes in the aroma or consistency. 

 

On February 20th, the day of my original starters' 23rd feeding, I observed even more bubbles in the original control starter. It appeared to have risen a little higher than the previous day when comparing it to the height of the original experimental starter. There were no changes in the aroma or consistency on this day. The two images below were taken just before 23rd feeding of these starters, around 8:00 am. 



This image shows the original control and experimental starters on February 20th.
 You can see that the control starter had risen much higher than the experimental
starter, and there are many bubbles visible through the side of the cup. 



This was the last image that I took of any of my starters. This image shows the original
 control starter on February 20th just before the 23rd feeding. After this day, my original
 control starter's health began to decline rapidly. Each morning after this day, there were
fewer bubbles, no aroma, and it was not rising as high.
____________________________________________________________________________________________________________

The End

During this time, I observed little to no changes in either of my newer starters, so I did not take any pictures of them. I did keep up with the observations of all my starters in my lab notebook, but there were not any significant changes to give an update on. Once it was time to submit our samples for DNA sequencing, all four of my sourdough starters had rather thin consistencies with few signs of life. Although the original control starter had been rising some in previous days, it was nowhere near having a doughy consistency. Since none of my starters seemed to be healthy enough to send in a sample for sequencing, I decided to dispose of them. On February 24, I threw away all four of my sourdough starters. 

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