Stretch out your yeast dollar?

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puttster

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When I read that yeast can double every 90 minutes... seems like you could take just 1% of your usual dry yeast pitching quantity (0.11 grams from a 11 gram pack), drop it into a cup of old wort and in 10 hours it will have expanded back up to your usual pitching quantity.
If you have timed your new batch of wort to be ready at that time, pitch.
Then save the remaining 99 batches worth of yeast in a cool dry place. Bad numbers? bad idea?
 
You have just described a yeast starter. Search that on here about 80% of the forums about yeast are about starters.
 
When I read that yeast can double every 90 minutes... seems like you could take just 1% of your usual dry yeast pitching quantity (0.11 grams from a 11 gram pack), drop it into a cup of old wort and in 10 hours it will have expanded back up to your usual pitching quantity.
If you have timed your new batch of wort to be ready at that time, pitch.
Then save the remaining 99 batches worth of yeast in a cool dry place. Bad numbers? bad idea?

Yes, but it doesn't really work that way. That is kind of what growing from slants and frozen yeast does. But you have to go slow and start small or you will stress the yeast which can give you off flavors and possible mutations. It works so hard to eat all the sugars that it will burn itself out.
 
When I read that yeast can double every 90 minutes... seems like you could take just 1% of your usual dry yeast pitching quantity (0.11 grams from a 11 gram pack), drop it into a cup of old wort and in 10 hours it will have expanded back up to your usual pitching quantity.
If you have timed your new batch of wort to be ready at that time, pitch.
Then save the remaining 99 batches worth of yeast in a cool dry place. Bad numbers? bad idea?

Yes, but it doesn't really work that way. That is kind of what growing from slants and frozen yeast does. But you have to go slow and start small or you will stress the yeast which can give you off flavors and possible mutations. It works so hard to eat all the sugars that it will burn itself out. It will then start putting out bad chemicals and you will end up under-pitching and pitching stressed yeast.

Having ruined beer by under-pitching (Diactyl - band-aid flavors/smell) I would highly recommend going slow with a small sample and taking days to build up a good sized starter before pitching.
 
Eh... that sounds risky to me. Saving an open package of dry yeast? I'd rather just repitch yeast from a previous batch any day. There are lots of ways to go about that.
 
Okay, I did some research, including the sticky, and saving seems like a good way to go. Q. In the sticky the bottom inch from the fermenter is stored in a (pint?) bottle in the fridge. It separates, which part is the yeast? Or does it matter, just dump the whole pint into the new wort?
Then after that ferments, save the bottom inch and repeat.
 
Use a pitching rate calculator to get in the right ballpark of how much to pitch from what you saved. Personally, I use quart mason jars to store. I rack as much beer off as i can, then swirl the yeast and dump it into a mason jar and stick it in the fridge. Decant the liquid off and pitch when my next brew is done. If your beer or saved yeast has a lot of trub, you may want to wash the yeast, but I usually don't need to. You will be able to see a line between the yeast and trub after it has been in the fridge overnight. The calculator will tell you if you need a starter or if you are good to pitch what is in the jar. Either way, make sure the yeast have a chance to slowly warm up to pitching temp before you throw them in your new wort.
 
Eh... that sounds risky to me. Saving an open package of dry yeast? I'd rather just repitch yeast from a previous batch any day. There are lots of ways to go about that.


Plus one !!!

It is incredibly easy to save a couple pints of slurry from your fermenter and pitch it into a successive batch.
 
I rack as much beer off as i can, then swirl the yeast and dump it into a mason jar and stick it in the fridge. Decant the liquid off and pitch when my next brew is done. .

Is the decant the good stuff or is the more solid looking stuff on the bottom the good stuff?
 
Decanting means to cool the slurry down so that everything seperates, and then pouring the excess liquid off the top.....this for me takes about 36-48 hours to have enough separation to dump out the liquid on top
 
decant = discard; pour down the drain

Well, you don't decant your garbage. Decant = pour the liquid off the top without disturbing the semi-solid stuff on bottom.

Anyhow, also keep in mind that someone is selling this yeast because they want to support home brewing while also making a living. (No not me.) So stretch your yeast $, but also buy some yeast once in a while, whether you need to or not.
 
Okay, I did some research, including the sticky, and saving seems like a good way to go. Q. In the sticky the bottom inch from the fermenter is stored in a (pint?) bottle in the fridge. It separates, which part is the yeast? Or does it matter, just dump the whole pint into the new wort?
Then after that ferments, save the bottom inch and repeat.

If the sticky just shows the trub just being stored in a jar this is similar to pouring your next batch of wort onto the top of the yeast cake from one that just finished. Lots of people do it, but you should only do it once or twice.

If you want to take it one step further you can "wash" the trub and pull off just live yeast to use later. You leave the the dead stuff, grain and hop dust behind. There are lots of threads and youtubes on this.

Basically you just dilute the trub with sterile water. I use about 3/4 a gallon that has been pre-boiled and cooled. So you have to plan ahead.

Start by pouring the water into your fermenter after you have transferred your beer to keg or bottles. Stir it around and pour it into a large sanitary container. Let it sit for an hour or so, to let it settle. Make sure you use good cleaning and sanitary techniques. I use a big 96 ounce juice bottle or a couple 2 liter pop bottles. I wash everything real well in hot soapy water beforehand (bottles and funnels) then final rinse it with Starsan.

After waiting for the hour or so you will see that it has stratified into 3 pretty distinct layers. A comparably clear layer at the top, a milky layer in the middle and a layer of thick stuff on the bottom. Carefully pour off the top two layers into another clean vessel (a juice container or pop bottle). Leave the thick settled stuff behind. It is just old dead yeast cells, grain dust and hop dust. The middle, milky layer is live yeast cells, which float and take quite a while to settle.

At this point you could have poured it into a handful of smaller vessels and stopped there. You would have a handful of containers of yeast to use for starters and share with friends. I usually repeat the above steps at least one more time to leave as much trub as possible behind. I shake the liquid around let it sit for a couple hours then pour it into a bunch of 12 ounce or 16 ounce clean, Starsan rinsed pop bottles. Some people use mason jars. These will keep in the fridge for months. The only drawback is that after doing this a few times you will have a lot of yeast bottles taking up a bunch of space in the fridge.

I have heard recommendations that you can use washed refrigerated yeast for 6 months or so. But I have made starters with washed yeast that was over a year old (which may be stretching it). I started slow with a cup of low gravity starter wort (1.025) wort and built it up to a liter or two of 1.040 wort.

From one batch of washed yeast you can have 5 or 6 bottles of yeast to use. If you wait a few weeks, all the good, clean yeast will settle to the bottom of your containers. You will probably have somewhere in the neighborhood of 2-3 teaspoons in each container. You can leave it as is or pour off the top liquid and combine these jars to have more yeast in a single bottle and get back some fridge space. You can even pour off the top liquid and freeze the slurry in centrifuge tubes to keep it for what they say is a couple years (40ml thick slurry, 10ml glycerin, 50ml water for two 50ml centrifuge tubes).

The general consensus is that you can wash yeast 6 or 7 times before you should be replacing it with fresh from the manufacturer yeast. It can mutate or you can have wild things get into it. I have heard of commercial breweries using yeast 10-15 or more times.

Some people carry this a step further and create "slants" to freeze. A slant is made by taking a small amount of yeast and swiping it on a medium of agar (a gelatin like substance) in a tube that is "slanted" at a 45 degree angle. The sample is taken by dipping a small wire into the yeast and swiping it across the agar. It is grown for a couple days into small yeast colonies which are then frozen in the tubes. Again, there are youtubes on this. These can be frozen for years. Given the small size you can create quite a yeast bank in a small space. You can make a bunch of them from the same fresh batch and stretch it out for years. Starters are made by taking a bit (less than 1/100th of a teaspoon) of yeast from one of these slant colonies and building it up from there. If you make a bunch of slants from a freshly bought yeast vial, before pitching it into your first starter, you will always have yeast as fresh as new.

To make a starter from any washed yeast you pour most of the liquid off the top down the drain (decant). You then pitch the yeast slurry from the bottom into your starter. Think about how much you have and compare it to how much you would get in a White Labs or Wyeast container and adjust your starter appropriately (start small/low and build up or start normally). You can go to one of the yeast calculators like Mr Malty or the one in Beersmith for assistance. If you make the starter a few days in advance, you can put it into the fridge for a couple days to cold crash it and to let the yeast settle to the bottom. Then pour off the starter beer and pitch its yeast slurry into your fresh wort.
 
Wow, nice detailed post above BitterSweet...

My only comment would be to substitute sanitary for sterile.

In a nutshell, one can wash, make starters, freeze yeast, make slants, and all sorts of possibilities.

I find merely collecting yeast slurry from the fermenter in a sanitary fashion, pouring the beer off the yeast and repitching the slurry effective and easy.

As with most things homebrewing, plenty of pros and cons and opinions vary.

Pros of washing yeast are trub and hop debris reduction, while the cons would be more handling and risk of contamination.

Pros for reusing slurry would be that it is extremely easy and storing yeast under beer may be better than water.

Ymmv, it is said that the yeast can mutate after 6 generations or so. Whether it mutates for worse or better depends on your goals lol
 
Wow, nice detailed post above BitterSweet...

My only comment would be to substitute sanitary for sterile.

In a nutshell, one can wash, make starters, freeze yeast, make slants, and all sorts of possibilities.

I find merely collecting yeast slurry from the fermenter in a sanitary fashion, pouring the beer off the yeast and repitching the slurry effective and easy.

As with most things homebrewing, plenty of pros and cons and opinions vary.

Pros of washing yeast are trub and hop debris reduction, while the cons would be more handling and risk of contamination.

Pros for reusing slurry would be that it is extremely easy and storing yeast under beer may be better than water.

Ymmv, it is said that the yeast can mutate after 6 generations or so. Whether it mutates for worse or better depends on your goals lol


Good point on the terminology. I made a couple changes.

I agree with the points on using the slurry. I have never refrigerated any so I don't really have any idea of how long it is good for. I do know that if you are going use it without storing, you should use it right away. I have had slurry sitting out go bad after a couple of days (and it stinks).

One point I don't think I mentioned (because it is probably obvious) is that one of the best things about washing and banking yeast is that you can use different yeasts at will. If you only use Saison, Kolsch or some seasonal yeast once or twice a year and you washed the yeast after the last batch, you have some ready to go, without having to run to the supplier and spend $$.
 
On this batch I put half the yeast in the pot and half in the fermenter. After racking I poured the bottoms of the pot into a pint jar. It is settling, about half liquid and half solid. Would this work as well as waiting for the bottoms of the fermenter?
 
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