Yeast Harvest Question

[hwangnyc]

Hello Everyone,

Quick question regarding yarvesting yeast. After the yeast has been harvested and placed in a jar what is the risk of exploding bottles? Also where should i store the yeast in the fridge? Should i make a blow off tube or places an airlock on the yeast jar? Thanks in advance!

 

[digdan]

Temps strictly control the metabolism of yeast. So putting yeast in a fridge makes it eat very very slowly. The slower it easts the less pressure it occures over time. You can also crack your container and recap it to release pressure.


If you give your yeast no food then it will simply starve to death. So you want to give it ample amounts of food, but make sure it nice and chilled so its metabolism is lowered.

Storing yeast does play a hand in god. You simply will kill those yeasts that are not as cold tolerant and have higher metabolism.

I farm yeast into small test tubes. I keep those in a fridge that is very very cold (not freezing, freezing bursts yeast cells). I then step them up at an increment of 10x until they are ready for my 5 to 10 gallon batches.

Some good advice is to just brew the same style of beer three weeks in a row, throw out the yeast strain and and buy a new yeast strain. That way you can re-use your yeast strain (and its already started) until its mutated to the point you should buy a new one anyways. I used one strain of yeast (English Ale) for over 8 brew sessions. It eventaully warped the flavor of my beer horribly.

 

[Mike-H]

If you give your yeast no food then it will simply starve to death. So you want to give it ample amounts of food, but make sure it nice and chilled so its metabolism is lowered.

Hmm, can anyone verify this statement? I was under the impression that yeast goes dormant and does not need food to survive. How does yeast survive dry/and or liquid in those viles without food based on this theory?

"3. Sedimentation - The yeast enter this stage once the sugar level starts to drop. The yeast drop out of solution and become dormant, flocculating (dropping out) to the bottom of your fermenter or bottle forming sediment. Again, the yeast go dormant, they do not die. If additional sugars are added the yeast will go full-throttle again."

http://homebrewzone.com/beer_yeast.htm

 

[homebrewer_99]

I think that was just his way of saying they're no longer active...not that they really die.

If you washed your yeast then you've reduced any residual sugars and there is no risk of exploding bottles.

 

[MariaAZ]

Just out of curiosity... is the reason homebrewers reuse yeast for only a certain number of times due to our general inability to keep things absolutely closed? If yeast constantly mutates, how do the yeast "manufacturers" produce consistent strains?

 

[homebrewer_99]

We don't have the sterility of a lab in our kitchens and basements, etc.

I wash and reuse almost all my yeast.

I've had some go bad recently, but it was an experiment with a dry yeast. The 3rd batch went bad.

What I did was wash my yeast a second time leaving only water (clean and clear) on top of the yeast versus a slightly yellowed beer/water mixture.

My conclusion is that by leaving a little beer/alcohol/water as a barrier versus plain old sanitized water is actually more safe. Maybe this should come under lessons learned.

 

[cwixon]

I put the yeast harvests in a sanitized mason jar. for a lid I just rubber band some seran wrap over the top. Then into the fridge they go until I make them into a starter.