I don't know if this is even possible so I'm going to ask the question. I propagate my own yeast and was wondering if it's possible to contaminate the yeast in a peatry dish? I know that when foreign microbes get in the dish the will start their own colony along side the yeast, but will they somehow mix with the yeast and ruin it? The last batch that I brewed ended up with a sour taste and I have my doubts that I took enough care when I propagated the yeast even though there doesn't appear to be anything else growing in the dish. I just want to make sure before I through it out and buy more yeast.
Thanks, Mike
Thanks, Mike