Yeast From Commercial Beer

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What is the best way to get yeast from commercial beers?. And is it worth the effort as dry yeast is so cheap and easy to use?
I don't think you will have much success, most comercial beers that are bottle conditioned ie: coopers, are pasturiesed after fermentation and then inocculated with a different strain of yeast for the bottle conditioning. This strain of yeast would not give you the same flavour profiles as the one that they used for fermentation.

However that is not to say you can't do it. Just be aware that because of the very low levels of viable yeast in the bottle you would have to do several starters beginning with a small quantity of wort and stepping up to a 2lt starter over several days.
Hope this helps
Hey SJW, you can give this a go! I dont know how successful it is. <_<

This is from Grumpy's website.

Propogating Yeast From Commercial Bottles
You can propogate the yeast from a commercially produced bottle conditioned beer quite simply. A commitment to cleanliness is all that is required.

First understand that yeast is not an ingredient, it is what is making your beer. There are as many different yeast strains as there are people on the planet. They change constantly, so the breweries tend to use pure strains that have been tested over time.

When trying to copy a particular beer, it follows that if you get the yeast right, you can be forgiven for not getting other things exact. The reverse is not true at all, you may get the ingredients spot on! If you don't use the right yeast, it will not get as close as it might.

1. Drink 80% of the beer from a bottle (by pouring in to a glass) of the one you wish to copy, ensuring that the sediment is not disturbed too much, cover and allow to stand at room temperature.

2.Sanitise a glass bottle, rubber bung, small funnel and airlock with One-Shot or similar. Allow solution to stand in the bottle until ready to use.

3. Bring 600 Ml water to the boil in a saucepan and dissolve into it, 60 G malt extract. (Two Dessertspoons) Simmer for a minute or so stirring to avoid burning and caramelisation then remove from the heat.

4. Empty the sanitising solution from the bottle then 1/2 fill the bottle with the hot malt extract via the funnel. (no need to rinse ortho-phosphoric)

5. Cover and cool the solution in cold water to about 24 deg C. Once cool, vigorously shake the bottle for about 30 seconds to aerate the extract wort.

6. Once you are sure the temperature is within limits, pour what is left in the bottle you drank into your starter solution, via the funnel, place on the bung and airlock and wait a day or so.

7. Brew the beer only when the yeast is in it's active stage and only after you have poured a little into a glass and given it the taste and smell test. Then you can
I've had a go with CUB's Sheaf stout, but chucked it cause it smelled funny(at the time) like rotten eggs......
I've managed to culture yeast from Duvel, Fullers 1845, Young's Special London Ale and Cooper's beers.
When using the recultured yeast in similar brews it has added the right flavour profile to the style.

Someone who knew someone in Coopers got it from the horses mouth that the yeast in Coopers Sparkling Ale, Pale ale and Stout is all the same and is used in fermentation and in conditioning. It is not pasteurised. I have used the yeast from the sparkling ale to make a very close copy of that beer.

Cheers - Snow.
I tried this yesterday using dregs of 2 stubbies of Coopers pale ale.
I followed Grumpys instructions to the letter but came home this arvo expecting to see some action in the bottle but nothing. :(

Couple of points i might have got wrong in the instructions.
I used 2 desertspoons of Coopers light malt extract powder. Is that correct?

The temp when i added the dregs may have been 1 or 2 deg C over 24.

I have been brewing coopers pale ale kits for the last 6 months or so & would like to see if using the yeast from the commercial bottles give any taste difference.

Any advice?

i had the same problem late last night when doing a grumpy's boston cream :blink:
my starter of 3 stubbies didnt seem to be to active after 30 - 34 hours
but my brew was ready....
so i pitched anyway.. :eek: ????

if the brew doesnt take off, is it alright to repitch with a rehydrated dry yeast that was supplied (safale 33).?

Making starters from commercial beers is always a learning experience. You never know exactly how long it will take to fire up, how much active yeast is left in the sediment on the bottom of your bottle and how the beer was handled by carriers and the bottleshop.

Always use the sediment from as fresh a bottle you can find, use the sediment from two bottles if possible to maximise the live yeast count, make a small step first, say 100 ml, and step to a litre once this is rocking, use 1.040 og wort, be as careful as you possibly can with your sanitary procedures and only pitch when each step has reached krausen.

Do not pitch a starter until you are sure it is at krausen.

Often, a starter will not be ready when you are ready to pitch, this is why we always have a backup dry yeast or two in the fridge.

If a starter is not ready to picth, use the dry yeast, allow the starter to ferment out, store it in the fridge, then 24 hours before brewday, pour off the old beer, pour in fresh starter wort , leave it somewhere at 22 deg and it should be kranking ready to use the next day.

Kong, if there is no activity (the starter wasn't working, so I don't expect any activity) within 24 hours pitch the dry yeast. So long as you have been careful with sanitising everything, your beer should be ok.
Thanx PoL
when i got home from work yesty there was a thin krausen of about 3-4mm, it didnt look like there was much yeast multiplication in the bottom of the bottle.!?
i made 3 stubbies straight up to 1 litre :( so maybe that was my problem..?
well i wil assume i pitched a dud, so essentially if all was sanitized.. all i have done is add an extra 100g of light DME.. yeh.?

is 20 hours usually enough for a commercial starter to get going once pitched.?
(pitched at 27degC and bought down to about 21degC over night)

I'll rehydrate my safale tonight and pitch after i've given the starter approx 22 hours to take.

is that a suitable plan.? :beer:
Reread all the stuff about making starters, Batz posted an excellent thread some time ago.

Brewing a starter from commercial beer will follow its own time table, not yours or mine.

The speed it will get to krausen, will depend on how much viable yeast you have added to the starter. I have had a starter take seven days to krausen, others have fired up within 24 hours.

The easiest way to check and see if it is working, every time you pass the starter bottle, give it a shake, and when there is lots of co2 leaving the airlock, foam on the top etc, it is time to pitch or step up. Shaking also adds more oxygen to the starter.

As the yeast becomes active in your starter, the wort goes cloudy, CO2 is produced and foam appears on the top. So, your 3-4mm of foam may mean it was active. The amount of sediment on the bottom is not a good guide as to whether the yeast is active or not, you won't see much extra sediment on the bottom as the active yeast will be mainly in suspension.

Yes, go home tonight, check your beer, if not working, add your dry yeast.
Cheers mate,
good to have knowledge on hand when going into uncharted waters.
still no action by 10pm last night, so i'd had my S-33 rehydrated and ready and pitched around 10:30.
woke up this morning and opened the brew fridge to find the airlock firing every 1-2 seconds!!
there was a slight hint of banana/estery type odour <_< not too sure which one of these it was, but it wasnt too bad.
Question; is it an issue to have re-aerated after 24 hours to pitch the S-33..? also... if in fact the recultured coopers was just a slow beasty, is there going to be any issue with the 2 yeasts working together.? :unsure:

You did the right thing.

Maybe the starter finally got its act together, and is working in tandem, maybe not.

Often there will be unusual aromas coming out the airlock, wait till you do lagers, you will swear someone farted in your fermenter. Just make sure it is fermenting at the right temperature range for your yeast.

If you aerated well at the start, there would be no need to do this again when pitching the dry yeast.

There will be no issues with the two yeasts working in tandem. Some of the commercial liquid yeasts are actually two different yeast strains.
so i spose in the long run that could be my only issue.. that i re aerated.
ohh well will wait and see..
fingers crossed
Joined: 20 Apr 1997
Posts: 304

Posted: 05 Oct 2004 17:07 Post subject:


In short...he's wrong.

As with all our bottle conditioned ales, Coopers Sparkling Ale is not pasteurised!

The pasteurising process would kill the yeast, preventing secondary fermentation leaving you with flat beer.

Paul - Coopers Brewery

Paul - Coopers Brewery

Joined: 20 Apr 1997
Posts: 304

Posted: 11 Oct 2004 11:38 Post subject:


The same strain of yeast is used for both primary and secondary.

I got this from the Coopers forum
Well after 2 days my coopers yeast started working (i think). There was pressure in the airlock although not bubbling like the frementer does, & a fine white film (krausen?) on top.

That was enough encouragement for me anyway & i mixed up a pale kit & pitched the yeast. It was around 28 deg tho :p It went into my fermenter fridge so it would drop to around 20-24 overnight.

Anyway i came home today & its fermenting away as if id pitched a dry yeast so i figure its all good....Time will tell i guess. :)
"Well after 2 days my coopers yeast started working (i think). There was pressure in the airlock although not bubbling like the frementer does, & a fine white film (krausen?) on top."

Yeah I had the same thing with a Pale Ale starter but I got to figuring that with less wort you get less bubbles
I was thinking today, Whats the point of starting the yeast in a bottle? Is there any reason why you cant just mix up your brew & chuck a couple of bottles dregs in?
Good point, and would serve you as a launching pad into the realms of yeast culturing.

With the dregs out of a commercial beer there are a very small amount of yeast and unknown quantity of viable alive yeast.

When you pitch yeast into your brew, you want a large quantity of viable happy hungry yeast rearing to go and convert your wort into beer. The sheer number of active yeast outcompete any unwanted bacteria or wild yeast that may be hanging around for the party.

Wild yeast multiply very quickly, of an order 10 of that of brewing yeast. So, if there are any wild yeast around, and not much active brewing yeast, the wild yeast will quickly overwhelm your brewing yeast.

With brewing a starter from a commercial bottle, you try and be as careful as possible with sanitation, and start off small, say 100ml. Once this is going, then you step up in orders of 10 to 1 litre.

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