During the early daze of the pandemic I was having trouble getting what I needed to brew so among other things, I bought a brick of BRY-97. The exp date was Apr ‘21 so before trying it out on a brewday I decided I’d test a little to gauge viability.
To test bread yeast I can add some sugar and yeast to warm liquid and see the foam develop. So, I figured I’d try the same thing with this expired BRY-97.
I have seen bread yeast develop foam within 5-10 minutes. I am going on an hour and a half and see zero action with this BRY-97. [emoji23]
I know BRY-97 is known as a slow starter so I am going to leave it out and see how long it takes. Of course, wild yeast or other beasties might give me a false positive in a day or so. To try to provide a control I set a sugar water only sample to see which (if either) foam and when.
Place your bets….