This is how it all began,
I have a 100% rye starter for about a year now. I used a spoon that had some other dough on it, that dough was from a bag of flour that had mentioned at the bottom of the packaging, it had some leavening improvers. Assuming that's commercial yeast?
Either way, will this commercial yeast, should it be in my starter, wreak havoc on my natural wild starter?
Will the wild strands kill it off?
"Flour with Leavening Improvers" generally means baking powder and/or chemical dough conditioners.
Your sourdough will be unaffected.
Not withstanding @GdD's comment above, even if you just had a small amount of yeast on a spoon, I would guess that, after a year (and it doesn't take nearly that long), the bacteria and yeast you've cultured in your starter have a strong foothold. Dominant strains typically win. After all, that is really the idea behind a sourdough starter. Continue to feed, and I doubt you would ever notice it.
