Its just dawned on me that apart from the wild yeast route that people are turning to in our life of lockdown one can buy “commercial yeast” and its staring at us in the face. I just had a lightbulb moment and surprised it took me so long (I guess because I only use wild yeast) but I once experimented using this product with great results.
There is a probiotic called S. Balardii. It is actually a yeast with probiotic benefits. Its full name is Saccharomyces boulardii and was once thought to be a different species to S. Cerevisiae aka Saccharomyces cerevisiae aka bakers yeast. However it is so similar it is now classed as a sub species of S. Cerevisiae which makes it almost identical to bakers yeast!
However you won’t find it in your regular store or supermarket but you will find it in a lot of pharmacies or health food shops. Don’t know what brands are available to you where you live but in the UK this one is easily available.
Granted it is more expensive than your regular bakers yeast but you don’t need a lot. One capsule is enough for a poolish and given time it’ll raise a loaf. You won’t find any difference to when using regular yeast poolish style.
Another good idea is to use Kefir. Fermented milk made from kefir grains. Like a sourdough starter it is symbiotic and has yeast and bacteria. You need to buy one that is live and made from “grains”. If it doesn’t say fermented using grains then don’t use it. Simply make a preferment using kefir and flour and once its risen and bubble like a sponge its ready to use. This brand has been tried and tested by me - works a charm. If you brew your own then you’re good to go.