What do you think went wrong? Is there anything glaring in what I posted above? I'm guessing my initial starter was too big or that particular vial didn't have enough viable yeast to get going. I'm going to try another vial in a 250ML starter on the stir plate and see how that goes.
That's really hard to guess at what went wrong. You can try a 10% glycerine solution instead. Also make sure that your glycerine solution is at room temp when you combine it with the yeast. One more thing to try is a small starter (100 - 200 mL is good), and ensure that the gravity of the wort is around 1.030.
One quick question -- how fast did you thaw the yeast? If you did it slowly, you can try quick-thawing it in some warm water.
Other than that, it is really hard to say what could have happened. Hopefully some trial and error will help you to determine what step in your process can be corrected.
That's really hard to guess at what went wrong. You can try a 10% glycerine solution instead. Also make sure that your glycerine solution is at room temp when you combine it with the yeast. One more thing to try is a small starter (100 - 200 mL is good), and ensure that the gravity of the wort is around 1.030.
One quick question -- how fast did you thaw the yeast? If you did it slowly, you can try quick-thawing it in some warm water.
Other than that, it is really hard to say what could have happened. Hopefully some trial and error will help you to determine what step in your process can be corrected.
Thanks for the reply! I just tried a different sample in a 250 ML starter. I pulled the sample out, wrapped it in paper towel and let it thaw in the fridge all morning. That night I took it out and put it in the starter wort (which had also been in the fridge). I let it sit on the stir plate for 24 hours. I saw what looked like a krausen ring on the starter vessel. I just took a hydrometer sample. It only attenuated down to 1.044 from 1.048. It looks like there is a little more yeast than what I started with but it's really hard to tell. I assume the yeast weren't healthy enough to do the job.
I have the samples sitting in a soft cooler, a lunch bag type. It's got a thin layer of insulation and the samples are surrounded by ice packs. I'm thinking maybe this isn't insulated enough and the frost free cycle killed all my samples? From what I've read it would seem more likely that this would be the case.
I'm going to try using a 50ML starter at 1.020 and giving that a shot. I'll bump it up to 500ML and then give that another 24 hours and take a reading. I hope that some of the yeast is still viable.
If not, I'm going to let everything thaw, dump the samples, soak the tubes in PBW and try again with some more harvested yeast. This time inside a better cooler, like a foam type.
I don't feel this was a waste of start wort. I just put the wort into jars and put them in the pressure cooker to re-sterilize. I figure, the dead yeast will be good nutrients and the wort still has plenty of sugars in it!
Location: Westside..... CenCal - the country that'll never take away my guns or money !!!!!!!!!!!!!!!!!!!!!!!
Posts: 3,952
does anyone use beakers when building up the cells on a stir plate? im trying to figure out the best way to cover them in a sanitary fashioned. the first step-up i use a 250mL with a 1000mL over it, but once i step again, i don't have anything glass that can be autoclaved to keep on it.
Thanks for the reply! I just tried a different sample in a 250 ML starter. I pulled the sample out, wrapped it in paper towel and let it thaw in the fridge all morning. That night I took it out and put it in the starter wort (which had also been in the fridge). I let it sit on the stir plate for 24 hours. I saw what looked like a krausen ring on the starter vessel. I just took a hydrometer sample. It only attenuated down to 1.044 from 1.048. It looks like there is a little more yeast than what I started with but it's really hard to tell. I assume the yeast weren't healthy enough to do the job.
I have the samples sitting in a soft cooler, a lunch bag type. It's got a thin layer of insulation and the samples are surrounded by ice packs. I'm thinking maybe this isn't insulated enough and the frost free cycle killed all my samples? From what I've read it would seem more likely that this would be the case.
I'm going to try using a 50ML starter at 1.020 and giving that a shot. I'll bump it up to 500ML and then give that another 24 hours and take a reading. I hope that some of the yeast is still viable.
If not, I'm going to let everything thaw, dump the samples, soak the tubes in PBW and try again with some more harvested yeast. This time inside a better cooler, like a foam type.
I don't feel this was a waste of start wort. I just put the wort into jars and put them in the pressure cooker to re-sterilize. I figure, the dead yeast will be good nutrients and the wort still has plenty of sugars in it!
It sounds to me like your yeast viability coming out of the freezing process is too low/negligible. Try freezing a new batch and cut back on the amount of glycerine this time. Make sure to mix thoroughly. And try warming the frozen vials in some lukewarm water to quickly thaw them instead of slowly. All of that may help.
And yes, I think you are correct about the starter wort. Just re-can (i.e. re-sterilize) them and they can easily be reused. Good thinking.
does anyone use beakers when building up the cells on a stir plate? im trying to figure out the best way to cover them in a sanitary fashioned. the first step-up i use a 250mL with a 1000mL over it, but once i step again, i don't have anything glass that can be autoclaved to keep on it.
Just cover it in tin foil before you pop it in the pressure cooker. Leave a good length of tin foil to cover over the lip of the beaker, and you will be good to go.
Alright so I stopped by the LHBS yesterday and finally got the sticker shock from the dry yeast price hike. Last batch I bought was $1.25 each, this time it was right around $3.00 each. I usually stock up by getting 6 or so of S-05 and same of S-04, not yesterday!
So what would be the best way to culture dry yeast? I know you shouldn't use a starter with dry yeast, but in this case I think you'd want to. I also could just put a little dry yeast in each vial, add water and glycerin but I don't think that would produce healthy yeast. I figure they need to have nutrients and food before getting frozen.
I could also just make a starter each time from 1/4 of a packet but I'd be worried about the yeast viability on an open package.
P.S. Where is the best place to get a reasonable sized glass pipet (10 ml or so) with a bulb that an both be autoclaved (pressure cooked) My current setup is a graduated turkey baster, but it's plastic so it only gets a star-san bath, and is hard to fit in the flask at an angle.
__________________
"People should not be afraid of their governments. Governments should be afraid of their people." - V
Primary: Nothin Secondary: Shady Lord RIS, Water to Barleywine, Pumpkin wine, burnt mead Kegged: Crappy infected mild Bottles: Apfelwein, 999 Barleywine, Oatmeal Stout, Robust Porter, Robust smoked porter, Simcoe Smash
Hey pewter, I built a bank of s-04 and their dry wheat as well. I used half of the package to make a 1L starter at 1.04 OG . When it was complete I chilled it down in the frig, poured off the wort, and stepped it up again with 1.04. I then followed the steps using water and glycerin. For making the bank I used 30ml glass vials with screwcaps. I didn't use a pipette. Instead I got a set of glass lab measuring cups and used them for pouring into the vials. I've made starters with both the S04- and with rogue pac man and had amazing results with the finished product. In fact, I've been able to take a 30ml vial and make three starters out of them.
So what would be the best way to culture dry yeast? I know you shouldn't use a starter with dry yeast, but in this case I think you'd want to. I also could just put a little dry yeast in each vial, add water and glycerin but I don't think that would produce healthy yeast. I figure they need to have nutrients and food before getting frozen.
I haven't seen the answer to this anywhere, but I would tend to agree with you. Using yeast dry inside the vial probably won't work well at all. You need to start with healthy, rehydrated yeast and then add it to the vial with glycerine and water.
OR, skip all that, and just put a small amount of dry yeast in each sterile vial, and store that. Honestly, I think that would work just fine (and it would be a LOT easier!).
FlyGuy, great post! I have one question. I don't have the freezer space at this point. Instead of any cooler, do you think wrapping the refreezable ice bags around vials and wrap with a bugi cord will work?
__________________
If I had a nickel for every beer I drank....I would be retired already.
Linear Mode
