Top Cropping Yeast (in Pictures)

[Weizguy]

When I get my brewery up and running in Northern Mexico in a few weeks I'm renewing all my yeast stocks and already have a Wyeast 1768PC calling out to me. My house beers are going to be American Wheat with 1272 and UK special bitters with the 1768PC and also of course 1469 so I'll be skimming like buggery. Thanks for the thread Wolfy, edit: up to now I've been doing the lazy thing and just saving and pitching yeast cake but have been getting off flavours and poor stability in many of my batches, so this will be an opportunity to ratchet up my skills one notch. I was actually looking at a pyrex jug the other day.

:icon_offtopic:

C'mon Bribie, you're moving here, yet you're still dissing your chosen state like you don't want to make friends.

Mexico is, was and always will be Victoria. Not sure why you toad-lickers assume that NSW is now North Mexico. Maybe it's the bufotenine? Lack of distance perception?

Good luck with your yeasting skills, though, and I look forward to meeting you in Newie one day.

 

[micblair]

second skim vs dirt skim. I know which one I will be re-pitching from.

Just had this slurry counted at work using a hemocytometer and some trypan blue stain for yeast viability. The count came back as 1.3 billion cells/mL with perhaps only 1-2 dead cells out of the 70 or so counted. The sample required some serious serial dilution (1/1000) for reliable counting (even saw a couple of cells budding!).

Using Mr Malty's 'repitching from slurry' slider I was surprised to find that this sample fitted into the "thin slurry" end of the spectrum, as this settled out to be a nice cake which required a fair bit of agitation to rouse up once I decanted all but a few mm's of the beer which it was being stored under.

 

[Yob]

Just had this slurry counted at work using a hemocytometer and some trypan blue stain for yeast viability. The count came back as 1.3 billion cells/mL with perhaps only 1-2 dead cells out of the 70 or so counted. The sample required some serious serial dilution (1/1000) for reliable counting (even saw a couple of cells budding!).

Using Mr Malty's 'repitching from slurry' slider I was surprised to find that this sample fitted into the "thin slurry" end of the spectrum, as this settled out to be a nice cake which required a fair bit of agitation to rouse up once I decanted all but a few mm's of the beer which it was being stored under.

awesome... where do you work? Hospital? Arent those (hemocytometer) usually used for counting blood cells and the like?

 

[micblair]

awesome... where do you work? Hospital? Arent those (hemocytometer) usually used for counting blood cells and the like?

Chemist, Monash Uni, got my friend who's a microbiologist to do it. Not particularly difficult (after watching someone more skilled than I do it) if you we're thinking about trying it? Microscopes on eBay aren't too dear, just getting the hemocytometer is the expensive part, and maybe some accurate pipettes to carry out the dilution.

 

[micblair]

After I've grown the yeast starter ill take another measurement and hook up the camera so u can see the yeast in all their beautiful glory!

 

[Mike L'Itorus]

Bugger me with a badger. I knew top cropping gave a good harvest, of extremely viable yeast, but this is the first time I've seen a cell count done on it. Kudos.

Question, though; given the size of your sample, the cells/mL, and the viability....is there a particular reason you're going to do a starter? To match MrMaltys numbers (and, therefore, George Fix's)?

Just saying, 'cos wyeast quotes pitch rates significantly different....(ie, 1billion cells/5USGal (18.53L/5Gal, so people don't have to look it up..) for OG<1060)...Jamils numbers (assuming 100%viability) would be double this for a 1060 wort (208bil). Now personally, I think a single (even fresh as fresh can be) pack in a 1060 wort is stretching the friendship considerably....but lets consider a more 'normal' OG (with 'normal' being very subjective, and open to wide iterpretation). Let's say 1045. MrM's numbers on that would be 158billion cells required. Let's drop it to 1040..141 billion..... I don't know many brewers who, with a fresh, well handled activator, would bother doing anything other than directly pitch into 19L of 1040 wort. Go further, and drop down to 1035OG.....124 billion cells for 5 gal. For 23L (a smidge over 6 gal), it's 149 billion. So, an English Mild will need 1.5 packs, or a starter? Hands up anyone that's brewed a Mild, or a bitter, or any beer in the 1035-1040 range....a fresh smackpack in a well aerated wort at 1035-1040 goes of it's tits at 18c, and if you push the temp, it will try to crawl out of the fermenter in the middle of the night, and sacrifice your first born child to gor.

Not trying to start an argybargy, or have a stir (well, maybe a small one), and definately not trying to deflate micblair in any way, shape or form (good work again on the cell count, mate). But there are a lot of different sources for pitch rates (from homebrewers, semi-pros and professionals alike), and none of them fekkin agree. :lol:

Oh, just a final, slight dig.....in 5 gal of wort, with 100% yeast viability, the OG required (according to MrMalty) for 100 billion cells (ie, a wyeast activator) is......1.028. :blink:

Jumpmash, anyone?

 

[Malted]

slight [/i]dig.....in 5 gal of wort, with 100% yeast viability, the OG required (according to MrMalty) for 100 billion cells (ie, a wyeast activator) is......1.028. :blink:

Jumpmash, anyone?

Given that these folks are not using a set volume a la smack pack, how many mls of their top cropped yeast should they use?

 

[eamonnfoley]

fresh, well handled[/i] activator, would bother doing anything other than directly pitch into 19L of 1040 wort. Go further, and drop down to 1035OG.....124 billion cells for 5 gal. For 23L (a smidge over 6 gal), it's 149 billion. So, an English Mild will need 1.5 packs, or a starter? Hands up anyone that's brewed a Mild, or a bitter, or any beer in the 1035-1040 range....a fresh smackpack in a well aerated wort at 1035-1040 goes of it's tits at 18c, and if you push the temp, it will try to crawl out of the fermenter in the middle of the night, and sacrifice your first born child to gor.

Not trying to start an argybargy, or have a stir (well, maybe a small one), and definately not trying to deflate micblair in any way, shape or form (good work again on the cell count, mate). But there are a lot of different sources for pitch rates (from homebrewers, semi-pros and professionals alike), and none of them fekkin agree. :lol:

Oh, just a final, slight dig.....in 5 gal of wort, with 100% yeast viability, the OG required (according to MrMalty) for 100 billion cells (ie, a wyeast activator) is......1.028. :blink:

Jumpmash, anyone?

This debate occurs on all sides of the planet, quite regularly. My opinion:

1) Best practice is a starter, fresh yeast or not.
2) I think Mr Malty's spreadsheets are more aimed at white labs when estimating viability (or just overkill in general). Wyeast seems to hold up pretty damn well at 6 months of age - where Mr Malty would call it practically "dead".
2) Starters are critical for lagers - especially when being pitched cold.
3) I recently ran out of US05 and had to (on short notice) use a 6 month old Wyeast 1007 direct pitched into 16L of 1054 ale. It fermented quite well.
4) I think a fresh smack pack of wyeast and its 100 billion cells will "do the job" as indicated on the label. But I usually go for a starter. But its always a basic 1L job, even if the wyeast (ale) is a few months old and Mr Malty is calling for something bigger.

 

[Mike L'Itorus]

foles, are you a golfer? Two twos.....foooorrrree! Boom-tish. Come for the comedy, stay for the veal. :lol:

re your points...
2/ (the first 2/) I agree.
2/ (the second 2/. Oh my, this is turning into a Two Ronnies sketch) I agree.
3/ no comment, not familiar with this yeast
4/ it appears you agree with wyeast estimates, but make an Irish starter (ie, to be sure, to be sure).

1/, though.....I disagree. Case dependant. to clarify:

Best practice is a starter, fresh yeast or not.

I disagree with this. Overpitching, particularly with yeast biproduct dependant styles (ie, estery), will pretty much take out a lot of what you are trying to achieve....for example, english styles. The esters from the yeast are an integral part of the beer, and overpitching will strip that away. Same applies for German hefes. Overpitching can also lead to clarity issues, etc...

Don't get me wrong, underpitching is just as bad. But there is underpitching, correct pitching - at the low. middle, and high end of the reccomended range, and overpitching. And I think that doing a starter as a matter of course would, in many instances, lead to overpitching. Probably less noticable in beers that require a neutral yeast ferment (what many people call 'clean', but I so dislike that term. It implies that anything not 'clean' is 'dirty').

2c

 

[eamonnfoley]

as a matter of course[/i] would, in many instances, lead to overpitching. Probably less noticable in beers that require a neutral yeast ferment (what many people call 'clean', but I so dislike that term. It implies that anything not 'clean' is 'dirty').

2c

Was referring to overpitching with reference to the Wyeast rate, but not beyond the Mr Malty rate. A 1 litre starter on just about any yeast will not lead to what most consider as overpitching.

 

[Bribie G]

:icon_offtopic:

C'mon Bribie, you're moving here, yet you're still dissing your chosen state like you don't want to make friends.

Mexico is, was and always will be Victoria. Not sure why you toad-lickers assume that NSW is now North Mexico. Maybe it's the bufotenine? Lack of distance perception?

Good luck with your yeasting skills, though, and I look forward to meeting you in Newie one day.

:icon_offtopic: I have taken your advice to heart and burned my CDs, although I might keep one in the glove box in case I get lost in my new area and end up at Nowendoc or Mt George - but I expect my single head and only ten fingers will give me away there despite the din from the car :unsure:

 

[beerbrewer76543]

 

[micblair]

This debate occurs on all sides of the planet, quite regularly. My opinion:

1) Best practice is a starter, fresh yeast or not.
2) I think Mr Malty's spreadsheets are more aimed at white labs when estimating viability (or just overkill in general). Wyeast seems to hold up pretty damn well at 6 months of age - where Mr Malty would call it practically "dead".
2) Starters are critical for lagers - especially when being pitched cold.
3) I recently ran out of US05 and had to (on short notice) use a 6 month old Wyeast 1007 direct pitched into 16L of 1054 ale. It fermented quite well.
4) I think a fresh smack pack of wyeast and its 100 billion cells will "do the job" as indicated on the label. But I usually go for a starter. But its always a basic 1L job, even if the wyeast (ale) is a few months old and Mr Malty is calling for something bigger.

Couple of things I didn't mention:

I'm making a 44L batch, and according to the pitching rate (1 million cells x 1/mL wort x 1/degree plato) I would need roughly 150 mL of my what would be 2.6 million cell/mL yeast after a growth factor of 2 for a 5L starter which I may or may not hit. Guess we'll have to wait and see how the finish product tastes!

 

[eamonnfoley]

Couple of things I didn't mention:

I'm making a 44L batch, and according to the pitching rate (1 million cells x 1/mL wort x 1/degree plato) I would need roughly 150 mL of my what would be 2.6 million cell/mL yeast after a growth factor of 2 for a 5L starter which I may or may not hit. Guess we'll have to wait and see how the finish product tastes!

You probably dont need a starter, how much of your 1.3mill cell/ml slurry do you have ? Surely you have enough for 44L. 250ml slurry will probably do it.
5L starter seems like overkill.

 

[micblair]

60-85 ml but calibrated from equal volume of water.

 

[Mike L'Itorus]

60-85 ml but calibrated from equal volume of water.

It looks much bigger in the photo.

yeah, yeah. I know. That's what she said.

fair enough, carry on.

 

[Wolfman]

THis could be a crazy idea, as I thought of it this morning out in my shed after night shift, could you split the top cropping as per splitting Wyeast packs? I currenty split a Wyeast pack into 5 vials. I know it is hard to count how many cells. Still would it be possible to make up a yeast nutrient solution up and mix this with the yeast only, split into vials and store as per my Wyeast samples?

I'd be interested to hear if anyone does this currently or if anyone has some ideas on how it could be done.

 

[AndrewQLD]

THis could be a crazy idea, as I thought of it this morning out in my shed after night shift, could you split the top cropping as per splitting Wyeast packs? I currenty split a Wyeast pack into 5 vials. I know it is hard to count how many cells. Still would it be possible to make up a yeast nutrient solution up and mix this with the yeast only, split into vials and store as per my Wyeast samples?

I'd be interested to hear if anyone does this currently or if anyone has some ideas on how it could be done.

You can culture up a viable colony of yeast from very few cells so I can't see why it should be a problem with what you suggest, you might have to step up a few more times is all.

 

[freek]

I realize that I am reviving an old thread but what the hell.

So the yeast goes through a cycle where it builds up glycogen reserves at the end of fermentation in preparation for lean times. So this means if you top crop before fermentation has finished the yeast will not store well (its food has been cut off and its not ready for starvation).

What if you top crop before fermentation has finished, be sure to take a decent amount of beer/wort with it, bung on an air lock and give it two weeks (or so) before decanting the fully fermented beer off it? Would this not store similar to yeast collected after full fermentation? How much beer/wort would you need to take with the cropped yeast?

 

[Midnight Brew]

From my understanding when you top crop you usually scoop up a bit of wort anyway and that yeast is very active and will ferment that wort even at a slow pace when refrigerated. The idea of top cropping is that you crop immediately into another batch of wort so the yeast isn't slowing down in any way and is ready for what you throw at it. In saying that I can see your point about glycogen levels perhaps being lean.

In your case it really depends how you plan on storing the yeast. I think it's kind of against the point of a top cropping yeast to crop it then put it in a starter. I love top cropping because you get a really clean sample of that yeast in its most active phase. If you freeze your yeast, (which is really easy I might add) you are adding glycerine at a percentage to keep that yeast suspended in storage, thus helping out with the glycogen reserves.

Hope that helps without directly answering your question.