Piotr
Well-Known Member
I had and interesting discussion with my friend microbiologist, and he told me some interestingng things about yeast, that contradict some "common wisdom" about starters, for this post I will call them myths:
Myth no 1: Big Vortex
No, in fact you shouldn't stir the starter too strong. If you make big whirlpool, all the particles of the liquid stay in fixed positions, and there is almost no stirring action in the volume - as if there was no stirring at all.
Besides, big velocity makes damage to the yeast.
It is best to stir slowly, this way you get better air exchange and yeast health. Just a small dimple on the surface, that's perfect.
Myth no 2: Big Volumes
There is no need to step up starter to large volumes. You may as well grow yeast in comparatively small flask, but you must provide yeast with fresh nutriets: as they ferment out, you can decant the spent wort and add fresh wort on top of the yeast, and they will keep on multiplying.
Myth no 3: Aluminium foil
Aluminium foil is not the best medium to cover the flask, the air exchange is not sufficient. Microbiologists prefer to use a tight cork made of coiled sterile cotton-wool
What dou you think? True or false?
Myth no 1: Big Vortex
No, in fact you shouldn't stir the starter too strong. If you make big whirlpool, all the particles of the liquid stay in fixed positions, and there is almost no stirring action in the volume - as if there was no stirring at all.
Besides, big velocity makes damage to the yeast.
It is best to stir slowly, this way you get better air exchange and yeast health. Just a small dimple on the surface, that's perfect.
Myth no 2: Big Volumes
There is no need to step up starter to large volumes. You may as well grow yeast in comparatively small flask, but you must provide yeast with fresh nutriets: as they ferment out, you can decant the spent wort and add fresh wort on top of the yeast, and they will keep on multiplying.
Myth no 3: Aluminium foil
Aluminium foil is not the best medium to cover the flask, the air exchange is not sufficient. Microbiologists prefer to use a tight cork made of coiled sterile cotton-wool
What dou you think? True or false?