BeaverBarber wrote:I was living in Cambridge last year, and I tried building up a Pacman yeast starter from the bottom of Dead Guy Ale bottles that I found at the Beer Warehouse in King's Lynn, and it didn't work for me. A friend of mine had a yeast lab with a microscope, and he looked at the yeast from the bottom of the bottle and found no movement. I'm not saying don't try, but I didn't have any luck.
Hmmm .... yeast don't swim, they more ride the currents. Motility is not an indicator of viability for yeast and most bacteria. Vital staining (new methylene blue) will help judge viability, as will adding wort to the dregs and then identifying budding under the microscope.