Blowoff, first time using washed yeast and a yeast starter.

[benkozich]

Hello and thanks for reading, I recently brewed using washed yeast and a yeast starter, my first time doing both. The yeast is Wyeast 1056 American Ale, I pitched it at 80 degrees into a glass 6 gallon carboy and controled temperature using chest freezer with a Johnson Controls Digital thermostat set at 70 degrees with a 1 degree diferential. I work long shifts and when I came home to check my brew 24 hours later and it was at 69 degrees. I opened the fermentation chamber and found that the beer had experienced blowoff. I have the sensor for the thermostat stuck to the carboy between a gel freezer pack to help with keping an accurate fermentation temperature.

I am still wondering why I experienced blowoff? Did I pitch too much yeast from my starter? I swear that I have a ton of viable yeast in my washed jars, for more than I have seen on other posts with washed yeast, I have washed the yeast 2 times and see no trub and my yeast starter was out for 36 hours.

I cleaned and sanitized my airlock and wiped around the lip of the carboy with sanitizer hoping to prevent infection before replacing the airlock and carboy cap.

Any pointers on preventing this again, preventing infection since it was uncapped, or guesses why it blew off? Thanks.

 

[Rambleon]

Blowoffs are in no way a bad thing. How big was your starter? Chances are you had a lot of yeast and that combined with a really high wort temp got them active in a hurry. I suppose if you really wanted to prevent them pitch at a much lower temp (low 60's). That should help them to grow at a more reasonable rate.

 

[benkozich]

thanks for the reply. It was a 1000ml starter and it was pitched at 78 degrees.

 

[Cyclman]

Blowoff often means you had a very healthy fermentation start. In no way is it a problem, if anything the opposite.

 

[WoodlandBrew]

How much yeast did you add to the starter? Washed yeast is close to 2 billion per ml.

 

[benkozich]

I would say I had around 400ml settled in the yeast starter I made.

 

[benkozich]

This is what was left of the washed yeast I added to the starter because it wouldn't fit in the flask. I had over half a pint of washed yeast in the jar. I don't see any difference in layers other than the thin liquid film on top, this has been settled for 2 weeks. Oh and it blewoff again today. I cleaned the airlock, sanitized the mouth of the carboy and the cap/airlock again, I hope it doesn't get infected since the cap was off for who knows how long?

 

[WoodlandBrew]

That pretty much explains it. Lots of yeast and high temperature is the recipe for a blow out.

 

[benkozich]

Should I pitch the yeast closer to the fermentation temperature? How do I determine how much yeast I will need? Every recipe I have seen said to cool the wort to below 80 and pitch the yeast.

 

[WoodlandBrew]

Should I pitch the yeast closer to the fermentation temperature? How do I determine how much yeast I will need? Every recipe I have seen said to cool the wort to below 80 and pitch the yeast.

Yes, pitch at or below fermentation temperature. Pitching warm will encouage Trehalose production as the yeast cools. If you are fementing warm (about 65 degres F) then overpitching will likely result in a blow out.

 

[benkozich]

Yes, pitch at or below fermentation temperature. Pitching warm will encouage Trehalose production as the yeast cools. If you are fementing warm (about 65 degres F) then overpitching will likely result in a blow off.

Will that affect flavor?

 

[WoodlandBrew]

The associated stress secretion will directly impact flavor. The trehalose is a sign that the yeast are going into dormancy. The extra time the yeast are working adds lag and other effects associated with an unhealthy fermentation.

 

[bigelowsbest]

Make sure to use a blowoff hose whenever you're pitching with a starter. I work at a brewpub and we get blowoff on just about every one of our batches. One thing the brewmaster really stresses to me is to control pitch temp, as this is what has a large impact on yeast contributed flavor in the finished project

 

[benkozich]

Awesome, thanks for the help.