BitterSweetBrews
Tim Trabold
I had some success this week I thought I would share.
I am hopefully brewing a Kolsch this weekend, time permitting.
I am using some yeast I harvested (washed) in early August 2016 from a batch made in July 2016. I froze it in late September 2016. I had let it settle in a container (PET soda bottle) stored in the refrigerator for a couple months before I decanted the water on top and froze the slurry (look for my YouTube video to see how I did it). Today is Saturday, June 23 2018. It has been almost 2 years since I made the batch the yeast was harvested from.
I thawed the yeast 4 days ago on Tuesday evening and pitched it into 2 1/2 cups of 1.025 LDME wort. On Thursday evening I added 2 cups 1.040 wort. It was cloudy and when I stopped the stir bar and let it settle for 10 minutes there was just a little bit of yeast on the bottom and a some bubbles on the perimeter. On Friday morning it was pretty cloudy, I smelled it. There was a definite CO2 layer. There was still some bubbling on the sides but nothing really apparent. I added two more cups 1.040 wort last night (Friday).
This morning, Saturday, I have a 2 inch kreusen. I am attaching a picture. It is freekin awesome. The little bottle I used to freeze the yeast is next to the flask. It smells great.
![20180623_102109[1].jpg](https://cdn.homebrewtalk.com/data/attach/516/516896-20180623-102109-1-.jpg "20180623_102109[1].jpg")
The bottom line is that you can bank your yeast and keep it for quite a while. If done properly and kept in the proper conditions, I have proven that 2 years is not out of the question. I store my frozen yeast in my refrigerator/freezer, in a soft sided cooler bag with an ice pack to help moderate the frost free cycles.
Proportions are:
35% yeast slurry
15% glycerin
50% sterile (boiled/cooled) water.
I made a 100ML batch in a beaker with markings and split it into two 50ml containers. I now use 50ML centrifuge tubes.
I am hopefully brewing a Kolsch this weekend, time permitting.
I am using some yeast I harvested (washed) in early August 2016 from a batch made in July 2016. I froze it in late September 2016. I had let it settle in a container (PET soda bottle) stored in the refrigerator for a couple months before I decanted the water on top and froze the slurry (look for my YouTube video to see how I did it). Today is Saturday, June 23 2018. It has been almost 2 years since I made the batch the yeast was harvested from.
I thawed the yeast 4 days ago on Tuesday evening and pitched it into 2 1/2 cups of 1.025 LDME wort. On Thursday evening I added 2 cups 1.040 wort. It was cloudy and when I stopped the stir bar and let it settle for 10 minutes there was just a little bit of yeast on the bottom and a some bubbles on the perimeter. On Friday morning it was pretty cloudy, I smelled it. There was a definite CO2 layer. There was still some bubbling on the sides but nothing really apparent. I added two more cups 1.040 wort last night (Friday).
This morning, Saturday, I have a 2 inch kreusen. I am attaching a picture. It is freekin awesome. The little bottle I used to freeze the yeast is next to the flask. It smells great.
The bottom line is that you can bank your yeast and keep it for quite a while. If done properly and kept in the proper conditions, I have proven that 2 years is not out of the question. I store my frozen yeast in my refrigerator/freezer, in a soft sided cooler bag with an ice pack to help moderate the frost free cycles.
Proportions are:
35% yeast slurry
15% glycerin
50% sterile (boiled/cooled) water.
I made a 100ML batch in a beaker with markings and split it into two 50ml containers. I now use 50ML centrifuge tubes.
