Have I got enough harvested yeast?

I guess this question has been done to death and I apologise for that but I am getting sore eyes from reading on the subject and cannot get a clear answer in my head.

My aim was to collect yeast from a 750ml (26oz) bottle of Coopers Pale Ale for use in a 5 gallon batch of Pale Ale I intend to do.

I collected the bottom inch or so (30mm) of dregs and put this into 3.5 pints (1650ml) of 1.040 wort which was then put on a stir plate for a couple of days until all sign of activity stopped. I then carefully poured off the spent wort and added more wort to bring the volume back to 3.5 pints (1650ml). Stirred this again for nearly 2 days then put in fridge to let it all settle out to the bottom. I then poured off the spent wort and put a couple of litres of boiled water into the flask, gave it a good mix up and allowed to settle for 20 mins then poured off bulk of the liquid into another flask leaving some trud in the bottom of the original flask. I allowed this to settle out over night in the fridge then poured off most of the liquid leaving about 250ml (cup)in the flask. Gave this a good swirl and put into a 250ml beaker and allowed to settle out in the fridge overnight.

Result is I have 25ml of yeast in the bottom of the beaker.

I am really confused by using the Mr Malty calculator!!
I am intending to do an ale, 5 gallons and lets assume default OG of 1.048. Do I set the date to the day I collected the yeast?? I assume I have to use the tab 'Repitching from Slurry' ? If I play with the 'Yeast Concentration' slider it gives ml of yeast needed figures in the range of 50 - 76 ml.

I did this harvesting exercise as a trial run as I have more bottles and intended to do it without washing the yeast and paying great care to sanitation. My intent was to just step up and pitch straight into the fermenter.

My questions are many but am I reading Mr Malty correctly?
Is the 25ml of yeast going to be enough to just put into another starter (say 1000ml size) then just pitch into fermenter?

Sorry if I have rambled on but many things are unclear to me and any specific advice would be appreciated.

ps Putting the dregs of one 750ml (26oz) bottle into 3.5 pints (1650ml) of 1.040 wort appears to have worked great as it took off like crazy on the stirplate.

Yeah I'd say you had well more than enough. pic?

1650mL is really quite large for a first pitch from dregs. It sounds like it took off well enough, but when you're culturing small quantities of yeast like that you are always fighting against competing organisms. If you'd like to get into yeast ranching, I'd highly recommend Chris White's book Yeast. It covers all of this stuff pretty well.

I've not done a lot of bottle harvesting, but I likely would have pitched my first round into something on the order of 100mL. From there, step up to 500mL, then 2L. Your latter two steps can be standard 1.040 starter, but I'd keep the first one nice and gentle at like 1.020. You'll end up with a lot more yeast. That's all just for next time, though.

The date function on the Mr. Malty calculator is just an approximate way of setting the viability of the yeast. From a starter, your viability is quite high. Those dates are primarily intended for people using non-fresh smackpacks or yeast slurry. You are indeed reading Mr. Malty correctly, and 25mL will definitely be underpitching. The sliders are pretty loose and fast with their estimates, but without a scope and a haemocytometer it's tough to do better than that.

From here, I would do a few more rounds of starter until I got up to the kind of volume the calculator suggests (50-75ml). I'd do a 1L starter, decant, and do a 2L starter considering what you are starting with. That should give you about the right volume.

Hope this helps!

1 ozs of fresh yeast is probably plenty to pitch straight.

While I always recommend a starter for liquid yeast, the vials from White-Labs are about 35 ml volume (total), the yeast only takes up 20-25% of that, and they say that is direct pitchable; and that's after 4 months!

If you know the yeast is viable (and you do), pitch it straight without a starter.

Calder said:

1 ozs of fresh yeast is probably plenty to pitch straight.

While I always recommend a starter for liquid yeast, the vials from White-Labs are about 35 ml volume (total), the yeast only takes up 20-25% of that, and they say that is direct pitchable; and that's after 4 months!

If you know the yeast is viable (and you do), pitch it straight without a starter.

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From my understanding, the comparison to the white labs vial doesn't work. I remember hearing somewhere that their yeast is centrifuged and resuspended before packaging. Even if that's not how they do it, I can say from personal experience with a hemocytometer that they have a cell density _way_ above anything I've ever seen in slurry or sludge from a starter.

I've got to imagine that the dregs from his cooper's bottle had nothing more than a few billion viable cells at most, and even those were likely pretty old and tired. If that's right, the growth charts don't suggest that he'd hit pitching rate with just two 1650mL starter steps.

Anyway, he'll definitely get a fermentation if he pitches as is, but I do think it would be underpitching.

Thanks ever so much for your thoughts and I will do the process again using your suggestions. Looks like I will have no trouble getting the quantity of yeast but maybe just a few more steps starting from say 100ml volume and working up.

Well experiment time is over and I have just started the real attempt to harvest yeast from one x 750ml Coopers Pale Ale bottle.

As suggested I am starting with 100ml of 1.020 wort + 3cm of dregs from the bottle in a 500ml Erlenmeyer Flask on a home made stirrer ( cost me $5 to make and I just love it). Will update on success or not.

The Pale Ale from the source bottle must be just about at the right temperature to drink so I shall look at that task now.

Keep us posted.

No sign of life in the 100ml of wort on the stir plate after 36 hours. I did not see any dregs in the bottle this time but pitched it anyway. I had some yeast nutrient but forgot to use it.

This bottle was purchase from the local bottle shop and was never refrigerated . It reached temperatures nearing 40°C for a couple of weeks during the last heatwave here. Wonder if that had any effect?

I will let it go for another 24 hours and then maybe try another bottle.

el_caro said:

No sign of life in the 100ml of wort on the stir plate after 36 hours. I did not see any dregs in the bottle this time but pitched it anyway. I had some yeast nutrient but forgot to use it.

This bottle was purchase from the local bottle shop and was never refrigerated . It reached temperatures nearing 40°C for a couple of weeks during the last heatwave here. Wonder if that had any effect?

I will let it go for another 24 hours and then maybe try another bottle.

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Harvesting dregs is a fickle mistress. 40°C could have definitely made the yeast pretty dormant, though I suspect you might be able to get some life out of it. That said, for the sake of your sanity it might be worth finding a more protected bottle somewhere to get a healthier start. You can culture up from a single cell if you need to, but the sicker your start is the more work you've got to do to coax them up.

Thanks MalFet. I will search for a bottle with more evidence of sediment and better protected. For a brief moment I looked at the flask and thought my wort was taking on a lighter color but I think it was just wishful thinking. I will still give it a day or so - cost nothing.

Here is an update on how it is progressing.
I started with 100ml of 1.020 wort + 3cm of dregs from the bottle in a 500ml Erlenmeyer Flask on a home made stirrer. After about 36hours it did not show a great deal of cloudiness but there was enough there to make me think something was happening. I let it settle out overnight at room (cellar) temperature 22°C and then discarded most of the liquid just retaining a little to swirl the sediment in.
Made up some 1.040 wort with 750ml (1.5 pints) of water and 3/4 cup of DME in my 2Litre Flask and added the contents of the 500ml flask. It has been back on the stirrer for 24 hours and the photo is what it looks like now.
Significantly more bubbles/froth than 12 hours ago but not really cloudy like first time I experimented. I used a much smaller and weaker first starter this time. Also in the cellar this time and it is about 8°C cooler down there.
Any comments welcome?

http://www.dpreview.com/galleries/9557465081/photos/919583/pale-ale-harvest-001

el_caro said:

Here is an update on how it is progressing.
I started with 100ml of 1.020 wort + 3cm of dregs from the bottle in a 500ml Erlenmeyer Flask on a home made stirrer. After about 36hours it did not show a great deal of cloudiness but there was enough there to make me think something was happening. I let it settle out overnight at room (cellar) temperature 22°C and then discarded most of the liquid just retaining a little to swirl the sediment in.
Made up some 1.040 wort with 750ml (1.5 pints) of water and 3/4 cup of DME in my 2Litre Flask and added the contents of the 750ml flask. It has been back on the stirrer for 24 hours and the photo is what it looks like now.
Significantly more bubbles/froth than 12 hours ago but not really cloudy like first time I experimented. I used a much smaller and weaker first starter this time. Also in the cellar this time and it is about 8°C cooler down there.
Any comments welcome?

http://www.dpreview.com/galleries/9557465081/photos/919583/pale-ale-harvest-001

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Sounds about right to me; well done! I've got a cultured starter at about the same stage that looks pretty much exactly like the one you've got going. By my understanding, you generally want gentle growth and gradual steps, for both yeast stress and purity reasons. I was rather surprised that you described such explosive growth on your first round. I don't necessarily think that anything was wrong, but that typically hasn't been my experience with cultured dregs. The fast fermentation you saw before made me wonder if you hadn't picked up something else along the way. But, then again, who knows...yeast is weird. Keep us posted!

It is now 12 hours since I took the last photo and the froth and bubbles have gone and the wort has a yellow/brown color with a suggestion of whiteness. I have just turned off the stir plate and will let it settle out overnight (it is 2200hrs here). In the morning I will pour off most of the liquid and add about 1600ml of 1.040 fresh wort and see what that yeilds for me.


http://www.dpreview.com/galleries/9557465081/photos/920905/pale-ale-harvest-2

el_caro said:

It is now 12 hours since I took the last photo and the froth and bubbles have gone and the wort has a yellow/brown color with a suggestion of whiteness. I have just turned off the stir plate and will let it settle out overnight (it is 2200hrs here). In the morning I will pour off most of the liquid and add about 1600ml of 1.040 fresh wort and see what that yeilds for me.


http://www.dpreview.com/galleries/9557465081/photos/920905/pale-ale-harvest-2

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Consider giving it a touch more time to settle out, and if possible get it into a colder temperature (like a fridge). You'll still have plenty of yeast if you decant, of course, but by decanting early you'll have selected out the low flocculation yeast. This can change the character of the fermentation you'll get. Looks good!

I gave it 14 hours rest and it settled well. Not a great deal of yeast yet as shown in the following photo (excuse crappy walls background of my cellar brewery).

Have poured off all but about 400ml of liquid and then added more 1.040 wort to give a volume slightly over 2 Litres. Back on the stirrer again at present.

http://www.dpreview.com/galleries/9557465081/photos/922284/pale-ale-harvest-3

Sorry to bore many but I will keep updating this as for us learners it helps to see the attempts of others to harvest from one bottle of beer.

It has been stirring away for about 8 hours and looks like this now.

http://www.dpreview.com/galleries/9557465081/photos/922862/pale-ale-harvest-4-002

And after nearly 24 hours it looks like the following:

http://www.dpreview.com/galleries/9557465081/photos/924042/pale-ale-harvest-5-002

Looks good! You are officially a yeast rancher.

I have had the flask in the fridge cold crashing for about 12 hours and there is still some evidence of suspension in the bottom third of the flask.
There is just over 2 litres volume at present and a little under 1 cm of yeast layer in the bottom of the 2 litre flask.

http://www.dpreview.com/galleries/9557465081/photos/928312/pale-ale-harvest-6

I do not plan to use the yeast for about another 14 days.

Can I drain of nearly all the spent wort and put in another 2 litres of fresh wort and give her another run? This would mean not really stepping up the volume. Is this likely to be an issue? Could I expect the quantity of yeast to increase significantly? I do not have another larger vessel free at present and certainly not one for the stir plate.

Any advice appreciated.

el_caro said:

I have had the flask in the fridge cold crashing for about 12 hours and there is still some evidence of suspension in the bottom third of the flask.
There is just over 2 litres volume at present and a little under 1 cm of yeast layer in the bottom of the 2 litre flask.

http://www.dpreview.com/galleries/9557465081/photos/928312/pale-ale-harvest-6

I do not plan to use the yeast for about another 14 days.

Can I drain of nearly all the spent wort and put in another 2 litres of fresh wort and give her another run? This would mean not really stepping up the volume. Is this likely to be an issue? Could I expect the quantity of yeast to increase significantly? I do not have another larger vessel free at present and certainly not one for the stir plate.

Any advice appreciated.

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Looks good! If you are going to wait a couple weeks to use it, I would leave it in the fridge as is and then decant and re-step about four days before you need it. The two liters will be perfect...it will provide a little bit of growth, but more importantly will get the yeast nice and healthy for pitching. Unless you plan on using it in an extremely large beer, this should provide you with a reasonable amount of yeast.

Thanks Malfet.
It is going into 5 gals of Pale Ale.
Do you think I should seal it up or just leave as is? Beaker and neck of glass were sanitised at commencement of stage,

el_caro said:

Thanks Malfet.
It is going into 5 gals of Pale Ale.
Do you think I should seal it up or just leave as is? Beaker and neck of glass were sanitised at commencement of stage,

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A good piece of sanitized tinfoil has always been sufficient for me.