there are many bacteria that are white. i'm guessing if you were streaking down to individual colonies it may gorw much faster than yeast? hmmm, would be interesting to try and purposfully contaminate a streak plate to see the differences...
you're far more likely to contaminate with staph epidermidis or aureus or some other bacteria... but yeah, i guess you'll know when you make the starter
No - just kidding. Looks pretty clean and healthy! But can I have a closer view? A bigger photo? There's something on the top right (at 1 o'clock) I can't determine. Mildew, maybe?
How's the smell? Like fresh yeast like known from starters? Or different?