An Idea For The Fresh Wort Retailers

[Wortgames]

OK, I want 10% of the profits :lol:


I think it would be very very cool to be able to buy longnecks of unfermented wort of different styles. They would be ideal for making and building healthy starters, without having to do all that boiling and cooling and messing around that makes it such a pain for home brewers to build up really decent yeast colonies.

Of course, we could do it ourselves by simply bottling a fresh wort kit but I'd be concerned about infection - presumably a microbrewery is in a far better position to maintain a sanitary process.

Any thoughts?

 

[Dr Gonzo]

Doing this is easy at home.
I fill bottles from the fermenter after the cold break has settled out,
place them in a stock pot on the stove and slowly heat to near boiling.
Keep them at this temp for about 15 min then cap the bottle.

 

[Wortgames]

Hi Dr. G,

I regularly bottle unfermented wort, but I wouldn't say it was 'easy' at home.

If you want to make really healthy yeast starters for a 40 or 50 litre batch, then you need to be looking at probably 5 litres or more of starter wort, ie 6 or more longnecks per brew.

You can only really heat a small number of bottles at a time - not enough to be able to bottle an entire dedicated batch of starter wort 'easily' but probably too much wort to be taking out of your normal brew while still ending up with a decent quantity of beer. Besides, how many brewers want to go to the lengths of AG brewing just to produce starter wort which will be discarded?

I think it would be fantastic to be able to just crack open a longneck or two of AG starter wort to boost up an existing starter, without having to go to the trouble of brewing and bottling it myself.

 

[Batz]

I tip what is left in the kettle through my hopsock,then bottle this.
Yes it has break material in it,all the better to get a starter going,I used to just tip it out...what a waste.

Batz

 

[Dr Gonzo]

I regularly bottle unfermented wort, but I wouldn't say it was 'easy' at home.

Ok, easy for some hard for others.

If you want to make really healthy yeast starters for a 40 or 50 litre batch, then you need to be looking at probably 5 litres or more of starter wort, ie 6 or more longnecks per brew.

For a yeast starter i just run the first 5 litres or so straight from the chiller into a flask and pitch into this.
The wort i collect into longnecks I use as speise for bottling, not yeast starters. I still pull 6 longnecks from a 50 litre batch no worries. If you want 50L final volume in the fermenter, then just make a 55L batch.

Besides, how many brewers want to go to the lengths of AG brewing just to produce starter wort which will be discarded?

Why would you discard your starter wort? Don't you just pitch this into your fermenter? Thats the whole point of using starter wort that is the same as your main batch.

 

[Wortgames]

I thought the idea of making a starter in the first place was so that you can discard the undesirable by-products of the initial propagation phase. Otherwise why wouldn't you just pitch straight into the whole wort, the no-chillers have proven that lag time isn't necessarily a problem in terms of infection.

As I understand it the reason for using a starter wort that closely resembles the brew is to condition the yeast into fermenting it, so they don't have to mutate or struggle with adapting to a new environment.

I think most commercial breweries will pitch either the slurry, or even better, the separated yeast - I don't know that there would be many that would pitch the entire contents of the propagation tank, wort-and-all?

 

[Dr Gonzo]

I thought the idea of making a starter in the first place was so that you can discard the undesirable by-products of the initial propagation phase.

A starter is for building up yeast quantities. Why would you want to pitch a slurry full of stressed, mutated yeast and 'undesireable by-products' when you could pitch a starter at high krausen full of healthy, active yeast in suspension.

I think most commercial breweries will pitch either the slurry, or even better, the separated yeast - I don't know that there would be many that would pitch the entire contents of the propagation tank, wort-and-all?

I'm sure there are. It's called 'krausening'.

 

[Mr Bond]

when you could pitch a starter at high krausen full of healthy, active yeast in suspension.
'.

Thats what I've been doing all these years without any deleterious effects.
Thought thats what making a starter meant.

 

[Wortgames]

A starter is for building up yeast quantities. Why would you want to pitch a slurry full of stressed, mutated yeast and 'undesireable by-products' when you could pitch a starter at high krausen full of healthy, active yeast in suspension.

Who says the slurry contains a high level of stressed or mutated yeast? I guess the question is whether you consider the byproducts in suspension better than the byproducts in the slurry. My point is that if yeast did NOT produce any off-flavours in the propagation stage, there would be no reason at all to make a separate starter. It would be far easier to just let the yeast multiply in the wort they are there to ferment.

There is obviously a reason that the experts recommend a separate yeast starter, and I would say that it's because yeast produce off-flavours during the propagation phase which would otherwise remain in the beer. A starter allows you to build up the yeast colony, and then discard the 'tainted' brew, allowing a clean main fermentation with a large population of viable yeast that don't need to do quite so much reproduction before they get down to fermentation.

George Fix (who I basically consider to be the authority on just about everything brewing) clearly finds pitching a starter (or 'mini-wort') at high kraeusen to be detrimental to the resulting brew, and he recommends building up a starter, allowing fermentation to complete and then using the settled slurry - which seems to be exactly what the majority of commercial breweries do.

'Kraeusening' is actually a technique for priming an already-fermented beer prior to bottling or kegging, not for innoculating a raw wort.

 

[Thirsty Boy]

I thought that the only point of a starter was to get yourself the correct number of viable healthy yeast cells.

You do this by growing them up in a low gravity, prefferably 1.02-1.04 wort with plenty of oxygenation and agitation. A stirplate being ideal for both.

This gives the yeast time to multiply, build up sterols and energy reserves; and to do so without the stress of a high sugar and/or a high alcohol environment. .

You dont let the yeast actually ferment out, once they have used up all the available 02 and nutrients, they will go into a sort of a self preservation mode, muck about with the make-up, thickness and permebility characteristics of their cell walls, and start to use up thier energy etc reserves - that should be used for fermenting your wort.

The brewery I work for certainly doesn't propagate in wort of the same gravity that they will be pitching into! Nor do they let it completely ferment. They want healthy, super viable yeast

So 18-24 hours after pitching your starter wort, you either pitch it, put more wort into it or chill it down while the yeast is still in grow mode. If you dont want to dilute your actual batch wort with lower og, possibly tainted starter wort, fridge it, pour off the "beer" and on brewday take some of your final runnings or some from your kettle, boil it in an erlenmyer, cool it down in an ice bath (15mins total) give it a shake and pitch it into your starter jar before your main batch has even come to the boil.

It'll be well active before you have boiled and cooled your main batch. If you No-Chill, you don't even have to hurry

Then you get plenty of healthy yeast, no starter by-products/flavours and you get to pitch yeast that is already kicking when it hits your wort.

Of course, if that 1.02-1.04 ish wort came pre-packaged in a nice pet bottle - that would make life a whole lot easier!! Something for the Fresh wort producers to do with their final runnings instead of putting it down the drain??

 

[Brewer_010]

or chill it down while the yeast is still in grow mode.

This is exactly what I do with my starters...if you want a good start in a lager you need a few hundred mL's of slurry (according to Palmer). I guess a big starter wort of 3L+ might not be noticable in a heavy ale but in a lighter beer it might be noticed. I find it easy to fridgerate a starter when at high krausen (to floc out the yeast) then pitch just the slurry.

 

[Dr Gonzo]

'Kraeusening' is actually a technique for priming an already-fermented beer prior to bottling or kegging, not for innoculating a raw wort.

Actually, its both.

Quoting Noonan from his brewers glosary.
'Krausen - The period of fermentation characterised by a rich foam head. Krausening describes the use of actively fermenting beer to induce fermentation in a larger volume of wort or extract depleted beer.'

From his brewing procedure:
'When krausening, "new" beer equal to 10 percent of the primary fermenting volume is used to introduce active yeast for fementation. Krausening produces strong initial fermentation.
A yeast starter is the equivalent of krausen beer, but made up from yeast cultue roused into ten times its volume of wort. The 10 to 1 dilution is repeated each time strong fermentation becomes evident until the starter is at pitching strength. Yeast starters, like krausening, promote stronger and faster fermentation starts and blanket the ferment with CO2 much sooner than does pitching yeast sediment.'

I'd take Noonans advice any day over Fix.

 

[tangent]

I'd take Noonans advice any day over Fix.

Woohoo! A Jeebus wrote my brewbook moment :lol:

I haven't seen one of those since my rant on the old green website years ago

It always eventually comes to this if you pursue it for long enough. Then it's a matter of I'll see your Noonan & Fix and I'll raise you a Mosher....


Edit - whoops, just to stay OT:
i run some wort off at the and and freeze immediately for the next starter.
Sometimes I run some of the 1st wort off and chill that (heaps quicker to chill 1Lt) then split the active yeast starter with some of the fresh cooled wort , so I step up for a while. Then when the fermenter is cool enough it gets a guts full of starter.

 

[Wortgames]

So does Noonan advocate adding the entire contents (or the 'beer' portion) of a starter to the brew?!

If so, I fail to see the point in making a separate starter in the first place. What is the point of 'increasing yeast numbers' in a separate vessel then tipping it all into the main brew? Wouldn't the numbers increase just as well if you pitched the original yeast straight into the brew?!

Aside from the risk of infection from a longer lag time (as refuted by the number of no-chill brewers who are apparently still alive), the explanation must be that the early propagation phase of yeast produces undesirable flavours, and this is why brewers have always been keen to do the propagation away from the brew and pitch large numbers of 'clean' yeast, leaving the undesirable flavours behind.

Given that pitching slurry seems to be a far more common way of innoculating a brew than 'kraeusening', I would say it's more likely that any off-flavours produced in a starter remain with the liquid and not with the slurry (or with both, but the high numbers of yeast in the slurry make it more useful than the relatively 'sparse' yeast population in the tainted liquid).

 

[Wortgames]

I don't want to appear like a dog with a bone here, but according to John Palmer:

One recommendation when pitching a large starter is to chill the starter overnight in the refrigerator to flocculate all of the yeast. Then the unpleasant tasting starter beer can be poured off, so only the yeast slurry will be pitched.

and:

the composition of the starter wort and the main wort must be very similar if the starter is pitched at or near peak activity. Why? Because the yeast in the starter wort have produced a specific set of enzymes for that wort's sugar profile. If those yeast are then pitched to a different wort, with a different relative percentage of sugars, the yeast will be impaired and the fermentation may be affected.

 

[Dr Gonzo]

Then the unpleasant tasting starter beer can be poured off, so only the yeast slurry will be pitched.

If yeast produce such unpleasant flavours in a starter, then surely they will produce the same unpleasant flavours once pitched in the main wort. Might as well tip the whole batch out.

I can see the point of not wanting to pitch the liquid if the starter was made from DME or something, but...

 

[Wortgames]

I think the point is that yeast only produce these off-flavours in the early reproduction phase. That is why the wisdom seems to be to complete this stage elsewhere and pitch somewhere near the required population of yeast into the wort, where they can get on with the business of fermentation, not the off-flavour-producing business of propagation.

Also, you say you'd 'take Noonans advice any day over Fix', but the quote you provided looks more like a description of a little-used technique, and certainly not a contradiction of Fix - is kraeusening really Noonan's 'recommended' pitching technique?

 

[Dr Gonzo]

Are you saying that the slurry from a 5L yeast starter has enough yeast in it to take off straight away without having to undergo another reproduction phase in the main batch? So i guess you don't need to aerate your wort at all. You wouldn't even have a lag phase.

 

[Wortgames]

Well, according to Fix's calculations, these are the kinds of quantities of slurry he is talking about:



So for a 20L batch of lager with an OG of 1048 he is talking about 320ml of slurry, either from a (fairly large) starter or from a previous brew.

I guess you could compare the amount of slurry going in with how much slurry you end up with after the brew - if you pitch a small amount of slurry, then all that extra yeast is being propagated within the brew, along with any off-flavours. If on the other hand you pitch a slurry that is closer in volume to the amount of slurry you will ultimately end up with, there has been a lot less reproduction going on, with presumably less off-flavours being generated.

I doubt you could completely eliminate the propagation phase within the wort, as this would presumably require a starter equal in size to the wort - so that you would pitch the entire volume of slurry you would expect to get at the end - but I guess the trick is to keep it below a certain level.

 

[Malnourished]

according to John Palmer:
the composition of the starter wort and the main wort must be very similar if the starter is pitched at or near peak activity.

Why would you discard your starter wort? Don't you just pitch this into your fermenter? Thats the whole point of using starter wort that is the same as your main batch.

You guys are both saying the same thing!! :blink:

That said, almost any kind of starter pitched into wort is going to go through a growth phase, and it is preferable to do so. Too much yeast growth is bad, but not having enough yeast growth is also worth avoiding. There is such a thing as overpitching. You aren't going to avoid yeast growth by growing up a normal-sized starter and decanting the liquid off, nor would you want to.

From the BJCP Study Guide:
"If an adequate amount of healthy yeast has been pitched and the proper nutrients are present, there should only be one to three doublings of the initial innoculum"

From Mr Malty's Proper Yeast Pitching Rates site:
"I know a number of people dump a new batch on top of the yeast cake, but you're not going to get the best beer that way. Yeast do need some growth to result in the right kind of ester profile, etc"

I'm sure Fix and Noonan both say something similar.