I visited Heidelberg (Germany) in 2009 and attended a brewery tour at the Kulturbrauerei. I really liked their Kellerbier and I wanted to plan a clone brew. Inspired by the Kellerbier brewed by the Heidelberger Kulturbrauerei I wanted to make a similar beer myself.
First, I got myself a bottle of Kellerbier and isolated the yeast from the bottle. The brewer assured me that they use the primary yeast for bottling. After drinking the beer I transfered the dregs to a sterile sugar solution to have a kind of fermentation and then plated on agar. Unfortunately I can’t remember which kind of agar I used. I guess it was malt agar. Well, I got a acidic impression while examining the plates after growing colonies were visible. As I had a lot of work to do for my studies at that time I just forgot about the yeast and put the rest of the yeast in isotonic sodium chloride solution and stored it in my refrigerator.
Nearly a year later in the Spring of 2010, I found the tube and gave the yeast a second chance. This time, I used Ovomaltine a malt based beverage which is very well known in Switzerland as a starter media. I went with this kind of starter because I had no access to my normal brewing equipment. I used one teaspoon of Ovomaltine to 450 mL of hot water. I then transfered this DIY-yeast starter in three bottles. The yeast was added after the starter cooled down.
I racked the sediments after six days to a new bottle and added 50 g of sucrose and 400 mL of sterile water. There was a nice sediment visible after several days and the starter had a nice yeasty smell. So far so good. Now the really funny part: the yeast went back in the refrigerator because I had no time for brewing… The yeast finally got to work in August 2010. I dumped the whole sediment of the bottle in wort from another batch and pitched it after a week to the first clone recipe of my version of Heidelberger Kellerbier. I have to thank all the little cells for staying with me all that time. I still have the yeast on a agar plate in my refrigerator waiting for the next batch…
I am now planning a second version of the beer and I now found out that the brewery does not make the beer anymore. I might have the only yeasts left for that beer now. I will post my recipe for the first attempt in the future and publish the tasting results as well. Stay tuned.