I have a frozen yeast bank. Most of it is getting quite old now. I had a period where I didn't take the time to step up the frozen yeast in time for brew day, then a period of using dry yeasts, then about a 1 year hiatus from brewing while fixing up my house then making a relocation.
Well I took a 20 ml vial of my yeast. 5 ml yeast slurry from a starter, 5 ml glycerin and 10 ml water. I froze it on 2/23/12. I made steps of 250 ml 1.025 wort. Then .75 liter of 1.035 wort. Then a final step of 1 liter of 1.040 wort. Decanting the old each time. The starters did very well and I think I pitched a proper amount of healthy yeast.
The beer was 44.4 % Rahr 2 row, 44.4% white wheat, 11.1% red wheat. Magnum, Cascade and Saaz hops.
It was brewed on 3/14/18 and bottled today. The sample tasted quite good.
What I noticed is that WY1010 is supposed to have low flocculation yet my beer is very clear. Due to a month fermentation? Another thing is that it appears I got 87% attenuation. 1.039 OG and 1.005 FG Wyeast says attenuation 74-78. ABV of 4.46%. I'll take that for a nice summer beer. And since I moved last fall from RI to FL, I consider it almost summer now!
Anyway it appears that you can keep frozen yeast for 6 years!!!
Well I took a 20 ml vial of my yeast. 5 ml yeast slurry from a starter, 5 ml glycerin and 10 ml water. I froze it on 2/23/12. I made steps of 250 ml 1.025 wort. Then .75 liter of 1.035 wort. Then a final step of 1 liter of 1.040 wort. Decanting the old each time. The starters did very well and I think I pitched a proper amount of healthy yeast.
The beer was 44.4 % Rahr 2 row, 44.4% white wheat, 11.1% red wheat. Magnum, Cascade and Saaz hops.
It was brewed on 3/14/18 and bottled today. The sample tasted quite good.
What I noticed is that WY1010 is supposed to have low flocculation yet my beer is very clear. Due to a month fermentation? Another thing is that it appears I got 87% attenuation. 1.039 OG and 1.005 FG Wyeast says attenuation 74-78. ABV of 4.46%. I'll take that for a nice summer beer. And since I moved last fall from RI to FL, I consider it almost summer now!
Anyway it appears that you can keep frozen yeast for 6 years!!!