Active Starter

[Screwtop]

Seems there has been a little confusion recently regarding making yeast starters and yeast propagation or stepping. I see lots of posts regarding yeast starters and brewers referring to krausen as being some barometer of fermentation activity. While krausen can be a sign of activity it is not always present, it is usually more associated with stepping or propagation, often associated with the aerobic phase when yeast are budding/multiplying.

In making a starter I simply want to pitch actively fermenting wort to my fermenter. Went to check a starter today, in the sunlight shining through the window I noticed that the starter had reached an active stage and was ready for pitching when it occured to me that what I was observing is what I have tried to describe on AHB many times before and that new brewers could benefit from seeing what an active starter "looks like". So took some pics, hope this helps.

This is a 5 litre starter prepared for a lager. Previously it was propagated/stepped from 2L to 4L then dropped out, then the slurry was pitched into a 5L starter, the fermentation is now good and active and ready for pitching. Sun shining through the window provided a great light source, I shine a torch on the fermenting vessel to observe fermentation.

Click on the images for a better look. Would like to upload a vid but don't know how

 

[the_yobbo]

So, basically you want your starter to have little bubbles rising looking like it is a carbonated drink freshly poured?

Going slightly off topic.
1) Your starter was in direct sun light, aren't UV rays/sun light bad for our little yeasties?
2) "Previously it was propagated/stepped from 2L to 4L then dropped out, then the slurry was pitched into a 5L starter"... I didn't realise your meant to decant/dispose of the starter and only pitch the yeast sediment at the bottom of it. Would this make much of a difference to the brew?

 

[Murdoch]

So you would pitch the whole 5L of starter directly into the wort ?
The liquor fermented at room temp doesn't affect the beer taste ?
Just trying to get my head around the whole yeast/starter concept
I had planned to grow a starter to the correct volume, cool in fridge then decant off the liquor & only pitch the slurry

Thanks for your advice,pics & info

 

[Pennywise]

Going slightly off topic.
1) Your starter was in direct sun light, aren't UV rays/sun light bad for our little yeasties?

I was thinking the same thing, especially when pitching the whole starter. Also interested in this as I try to keep all my starters covered up and away from evil sunlight.

 

[Screwtop]

So, basically you want your starter to have little bubbles rising looking like it is a carbonated drink freshly poured?

Going slightly off topic.
1) Your starter was in direct sun light, aren't UV rays/sun light bad for our little yeasties?
2) "Previously it was propagated/stepped from 2L to 4L then dropped out, then the slurry was pitched into a 5L starter"... I didn't realise your meant to decant/dispose of the starter and only pitch the yeast sediment at the bottom of it. Would this make much of a difference to the brew?

So you would pitch the whole 5L of starter directly into the wort ?
The liquor fermented at room temp doesn't affect the beer taste ?
Just trying to get my head around the whole yeast/starter concept
I had planned to grow a starter to the correct volume, cool in fridge then decant off the liquor & only pitch the slurry

Thanks for your advice,pics & info

I was thinking the same thing, especially when pitching the whole starter. Also interested in this as I try to keep all my starters covered up and away from evil sunlight.

The starter had been in the fridge at 9C but I wanted to speed it up so brought it into the house to warm up. And no not concerned about flavours from warm fermentation, the temp by the window was around 18C.

I'm not concerned about light strike, firstly no hops in the starter so no hop protiens, secondly it was in sunlight for maybe an hour. Just where I had put it on the bench by the window.


Pitch slurry only if you want, then you are pitching yeast. For this larger I want to pitch a starter. What I did previously was build up the amount of yeast, dropped out, poured off the beer and then pitched the correct amount of yeast (slurry) to my 5L starter. Now that I have an Active Starter
it can be pitched and the lag phase will be as short as possible.

Why do people stress so much about yeast starters :lol:


Screwy

 

[felon]

Great photo's. :icon_cheers:

 

[Oatlands Brewer]

GOLD...Thanks Screwy.

I had almost the same looking thing bubblin away on my kitchen table on Sat night, it was my first starter ever, for a IIPA, i was under the inpresion that i shouldve been a foam spittin monster before i pitched it, but it never aventuated. so come pitchin time on sunday, in she went holdas boldas even shook the bugger up.....now the fermenter is a foam spittin beast...most active ferment ive ever had.

It was a 4 lt starter in a 20l brew

 

[Nick JD]

If you are pitching the whole starter, not just the yeast - why not just let the yeast "start" in the fermenter? Can you esplain why yeast will be different if it starts in a smaller vessel first?

Won't 5L of lager yeast at 18C be producing esters like crazy?

Do you only do this to save $5 worth of yeast?

What advantages to flavour are you achieving with these three steps?

 

[Oatlands Brewer]

Nah Nick the OG was 1080.....a bit to high to pitch the smack pack on its own

 

[manticle]

Seems there has been a little confusion recently regarding making yeast starters and yeast propagation or stepping. I see lots of posts regarding yeast starters and brewers referring to krausen as being some barometer of fermentation activity. While krausen can be a sign of activity it is not always present, it is usually more associated with stepping or propagation, often associated with the aerobic phase when yeast are budding/multiplying.

In making a starter I simply want to pitch actively fermenting wort to my fermenter. Went to check a starter today, in the sunlight shining through the window I noticed that the starter had reached an active stage and was ready for pitching when it occured to me that what I was observing is what I have tried to describe on AHB many times before and that new brewers could benefit from seeing what an active starter "looks like". So took some pics, hope this helps.

This is a 5 litre starter prepared for a lager. Previously it was propagated/stepped from 2L to 4L then dropped out, then the slurry was pitched into a 5L starter, the fermentation is now good and active and ready for pitching. Sun shining through the window provided a great light source, I shine a torch on the fermenting vessel to observe fermentation.

Click on the images for a better look. Would like to upload a vid but don't know how

View attachment 38880 View attachment 38881

Cheers. Useful distinction and pictures always help.

@Nick JD - my assumption would be that faced with such a large volume of sugar that amount of yeast might stress and produce flavours like acetylaldehyde. Obviously the proportion of sugar to yeast cells in the smaller starter is more in the yeast's favour which is why it is built up first.

This is my understanding as to why I do what I do (which is very similar to Screwtop's method). Happy to be wrong or have someone else explain it better.

 

[Stuster]

If you are pitching the whole starter, not just the yeast - why not just let the yeast "start" in the fermenter? Can you esplain why yeast will be different if it starts in a smaller vessel first?

Won't 5L of lager yeast at 18C be producing esters like crazy?

Do you only do this to save $5 worth of yeast?

What advantages to flavour are you achieving with these three steps?

If you start the yeast in a smaller quantity of wort, you have a relatively high amount of yeast cells present. These will rapidly produce conditions which will inhibit the reproduction of bacteria and so on. Pitching into a large quantity of yeast will do the opposite, meaning you may have enough bacteria etc present which may produce off flavours. It's really just a numbers game. You also need the numbers when you are fermenting a big beer like that, or you can end up with the yeast not being able to complete fermentation, leave behind sugars you want converted to alcohol, sugars which will may leave you with a sweet, cloying beer. You should also get your yeast up to the appropriate number so that when you are pitching them into the wort you then get the appropriate amount of ester formation for that beer style. With fewer yeast cells to begin with, you'll get more yeast growth and thus more ester production. Which you may or may not want. Again, it's about getting what you want out of the yeast by getting the right numbers.

You will be getting esters from that lager yeast at 18C. Personally, if I make a really big starter I hope that I have time to let the yeast drop out and pitch only the slurry.

 

[manticle]

I guess the other reason I do it is simply being prepared with enough cells before you make the beer - otherwise it may take a while to kick off and the beer may be prone to infection if the lag/reproduction time is too long.

 

[Nick JD]

Why not just pitch two packs of yeast?

EDIT: if Wyeast say their packs do 19L @ 1.060 is it because two packs will be overpitching? Do their lager packs contain twice as many cells as their ale packs? One would hope so with all the kerfuffle about pitching rates...

You will be getting esters from that lager yeast at 18C. Personally, if I make a really big starter I hope that I have time to let the yeast drop out and pitch only the slurry.

I just re-read it and I think screwy meant the ambient temp was 18C, not the yeast culture. You'd think so, not much point doing all this to eliminate esters produced by stressed yeast and then give them perfect conditions to produce esters.

 

[Screwtop]

You will be getting esters from that lager yeast at 18C.


Personally, if I make a really big starter I hope that I have time to let the yeast drop out and pitch only the slurry.

No, there is a crap load of yeast, plus it's a low gravity starter, no yeast stress. Also no budding/replication, straight to fermenting. Plus it is not a particulary stinky strain fermented warm, plus it has been in the fridge at 9 (as posted previously), only removed to warm it up a get it hiking for a couple of hours, then attemporated prior to pitching.

Depending on the style/gravity etc I sometimes pitch yeast (slurry) but in many cases I want an active starter. It's easy to adjust a recipe to allow for additional unhopped wort, plus a little sucrose to readjust fermentability.

I step yeast at warmer temps, larger or ale. While stepping up it was in the fermenting fridge with a couple of ales at 18.

Screwy

 

[manticle]

Why not just pitch two packs of yeast?

I use liquid yeast and I also reserve yeast from top cropping, splitting and slurry which needs to be stepped up.

2 packs is $30 (+ postage although I'll usually buy in conjunction with hops and grain etc) and not only am I thrifty by necessity, I'm also talking to a man who reserves his late hops for bittering for the next brew. I thought you understood tight brewers?

It's also about having the strains you want on hand too by the way. If I was using dried yeast (which I sometimes do) that required high cell counts then I would pitch two packs but liquid - no way.

 

[Pennywise]

I'm not concerned about light strike, firstly no hops in the starter so no hop protiens, secondly it was in sunlight for maybe an hour. Just where I had put it on the bench by the window.

Ahh of course, it's the hops, thanks Screwy. Will be a bit more relaxed with my starters now

 

[Screwtop]

Why not just pitch two packs of yeast?

EDIT: if Wyeast say their packs do 19L @ 1.060 is it because two packs will be overpitching? Do their lager packs contain twice as many cells as their ale packs? One would hope so with all the kerfuffle about pitching rates...



I just re-read it and I think screwy meant the ambient temp was 18C, not the yeast culture. You'd think so, not much point doing all this to eliminate esters produced by stressed yeast and then give them perfect conditions to produce esters.

For this lager I need a lot more cells than the 100 billion available in a fresh smack pack.

the temp by the window was around 18C.

Yes, you could have assumed that from reading the above :lol:

Screwy

 

[Nick JD]

I thought you understood tight brewers?

I thought I understood rich brewers!

The way I do it is to pitch the correct amount the first time and then bottle slurry. Each slurry bottle is an adequate pitch (there's enough yeast in one fermenter's trub for 4 brews) so it eliminates the need for complicated starters.

For $20 worth of yeast I can get 10 brews with a max 3rd generation yeast. $2 a brew ... that's tight isn't it? No dicking around with starters - although I must admit they are fun. Since I began bottling yeast I've stopped making starters.

 

[manticle]

I use that method too. I still make a small starter to make sure I have active, healthy yeast though. If dicking around bothered me, I'd buy beer.

 

[Stuster]

No, there is a crap load of yeast, plus it's a low gravity starter, no yeast stress. Also no budding/replication, straight to fermenting. Plus it is not a particulary stinky strain fermented warm, plus it has been in the fridge at 9 (as posted previously), only removed to warm it up a get it hiking for a couple of hours, then attemporated prior to pitching.

Fair enough. I didn't read all of your post, Screwtop. Just noted NickJD's question about lager yeasts at 18C and said what my practice was. I see your steps now and that makes a lot of sense.

One point about your post, you say no budding/replication but that is of course one thing we are often after in our starter - to increase the yeast numbers. I realise you are just doing this step to get the yeast raring to go after previously building up yeast numbers by the previous steps. Right?

Nick, how long do you keep your slurry for before using it?