yeast starter confusion

[hoppyscotty]

Planning on making a yeast starter for my next brew. The liquid yeast I have says its good for a 19ltr batch. Though we're aiming for a 19ltre batch we might end up with a touch more and its a high OG beer. This coupled with the fact I didn't put the yeast in the fridge immediately I just feel I want to give the yeast the best chance when I pitch it.

I've looked on a number of YouTube and other sources and there are some differences and I'm not sure what I need to do. Some say you need to skim off the spent yeast before pitching, so involving cold crashing, taking off the spent yeast, and making a slurry to pitch whereas others just make up the starter and pour right in. Also some say you need a stir plate and continually stir for the 24 to 48 hrs or so before pitching, some say the swirl when you walk past method if fine and others say no need to do anything and some say depending if you're using the stir plate, swirl when you walk bay or do nothing method then that affects the amount of DME and water you start off with.

Am I over thinking this? I'm not planning on storing the starter so just making up 24 to 48 hrs or so before brew day and don't have a stir plate. So should I just mix up in a 1.040 solution of water/DME and swirl when I walk by and directly pitch?

Thanks.

 

[DocAnna]

So I'm not an expert - but I have been experimenting with starters and have tried most of these options. This is a really good write up of the options here How to Make a Yeast Starter .
The short version is you can pitch the whole lot, or you can cold crash and pitch just the sediment, the main difference is the added volume of the starter liquid. To get the most growth a stir plate is ideal, and I do have one which works well, but it isn't essential. You can can give it a swirl whenever you can which won't in theory give the most growth but it will still help. I've done 72 hour starters and more recently did a 13 hour starter and pitched the lot while it was v active, with fermentation in the fermenter then taking off like a rocket.

As to the DME amount, 1g/10ml is the oft quoted amount though for a 1.040 solution it's actually a little more, but it doesn't need to be exact.
I hope that helps

Anna

 

[hoppyscotty]

Brill, thanks Anna. Will go for the simpler pitch everything in and swirl when I walk by method then and sounds like I shouldn’t be too far wrong.

 

[Galena]

What will the OG be and what was the manufacture date of the yeast? If it is high then you may need to build it up to enough cells so as not to underpitch, but if the manufacture is this year and you don't want to save any for another starter then if you make 1.5 litre starter with 150 mls DME that should give you enough for 19 litres with an OG of 1.060 in a single step.
As Anna says, better with a stir plate but not at all essential but you will need to shake it really well before pitching and shake as often as you can for the first 12 hours or so.
I always make it 3 days before I need it, aerate for the first 12 to 18 hours, then leave another day and let it settle out, this apparently allows the yeast to build up it's glycogen store as it prepares to go dormant. Then either just chuck it all in, or I prefer to put in the fridge for 12 - 24 hours to cold crash and then carefully pour off most of the 'beer' leaving just enough to shake it all up before pitching into the wort.
It is also said to be better to make sure the yeast is not warmer than the wort when you pitch as this can stress the yeast.

 

[nickjdavis]

You can do all or any of the above.

My only concern is your use of the phrase "skim off the spent yeast"....there is no "spent yeast"....all the yeast is valuable and the idea behind making a starter is to grow more yeast that is valuable. Hopefully what you meant was "to decant the excess wort".

OK....so.....different folks do different things....I guess it depends a lot on what fits in with their own brewing methodology....a lot of this turns into brewing dogma which is often difficult for newcomers to decipher and determine what is right and what is wrong. The truth is that often there is no right or wrong... someone will tell you that you must/should do XY or Z simply because that's what they do, either because it works for them or....because they are forced into doing that by the limitations/configuration of the brewing system that they are using.

So, having said all that...Lets take the simple one first....do you pitch the entire starter or do you decant the excess wort and pitch the remaining slurry into your beer?....I guess one key driver to this is what type of beer you are brewing and what size the starter is. If you have made up a 1-1.5L starter to pitch into 19L then the wort in the starter will only have a marginal effect on the gravity of the beer....i.e. the 1-1.5L isn't going to dilute it much. However, if you've made a 3 or 4L starter for a lager or maybe a high OG beer then the starter wort is going to dilute your beer down quite a bit....so you might want to decant the excess wort.

If its your first time out and your starter is reasonably small then I'd say keep things simple, make your starter 2 or 3 days in advance (give the yeast time to grow) and pitch the lot into the FV. At a later date when you have a bit more experience, perhaps you can then experiment with making the starter in advance, once the initial growth phase is over (or even when the starter has fully fermented out...though there is no real need to let this happen) throw the starter in the fridge for a couple of days which will drop the yeast out leaving clear beer on top....shortly before brew day carefully decant this clear beer leaving maybe half a litre left with the grown yeast. When you are ready, give it a swirl and pitch.

So...what about aeration....many folks get by perfectly well by giving the starter a quick swirl each time they pass, some swear blind that you need a stir plate and others will tell you that direct oxygenation with pure O2 is the only way to go. Stir plates seem to be popular and I guess fit in nicely with homebrewers love of gadgets and love of building things...they're not too difficult to put together yourself....however be aware that air only contains 21% Oxygen and as a result aeration by stir plate is only going to give you a certain amount of Oxygen in your starter....so don't be convinced by others that you desperately need a stir plate to do what you want to do. Sure using a stir plate is a lot easier than having to remember to give your flask a shake/swirl each time you go by it but hey...your beer will still be made even if you only shake the flask.

Regards the amount of DME/water....yeast growth calculators will tell you that you need bigger starters (i.e. more volume and more DME) if you dont practice any sort of aeration...but there are other factors as well....the age of the yeast, how its previously been stored for example that all have an effect on the viability of the yeast that you have...which in turn will effect the size of the starter needed. But for now....dont worry too much about that too much....as your experience grows you might then start learning more about yeast growth and then you might get in to building starters in steps.

 

[hoppyscotty]

This is great. Thanks all for your advice and benefits of experience. All great stuff for background knowledge. I do like to geek out on the underlying science so gives me plenty of research to go at and I like the keep things simple approach to begin with.

The beer is a double IPA and just concerned about the yeast as it’s all on the maximum limits in terms of what’s on the packet (volume and gravity) and the fact I didn’t put it in the fridge right away. But seems like a good practice thing to do anyway with liquid yeasts so a handy skill to have in the armoury.

 

[tld6008]

Just mix with the .040 solution and keep it at the recommended temp while swirling periodically

 

[The-Engineer-That-Brews]

Interestingly White Labs recommends adding adding yeast nutrient as well as DME to the starter, although I've not heard this mentioned elsewhere

 

[Galena]

Interestingly White Labs recommends adding adding yeast nutrient as well as DME to the starter, although I've not heard this mentioned elsewhere

Well the cynic in me would say 'they would say that wouldn't they' as they are selling it. I do have a bag of WL nutrient though which I have not used until recently except on high ABV ales and a lager. Yesterdays IPA has gone off like a rocket.

 

[Brewnaldo]

Bit of a bump here as I am coming into lager season and I wish to get a bit more precise, and as such have been reading about pitch rates etc. Now I havent made lots of lagers with liquid yeasts, but every liquid yeast starter I have done has been a 1 litre starter then pitch. Evidently from playing with calculators, this is on every occassion, a massive underpitch. Can someone tell me what they expect in terms of flavour from an underpitched lager yeast fermentation

 

[DocAnna]

Bit of a bump here as I am coming into lager season and I wish to get a bit more precise, and as such have been reading about pitch rates etc. Now I havent made lots of lagers with liquid yeasts, but every liquid yeast starter I have done has been a 1 litre starter then pitch. Evidently from playing with calculators, this is on every occassion, a massive underpitch. Can someone tell me what they expect in terms of flavour from an underpitched lager yeast fermentation

While not the answer you're looking for, with a couple of my lagers earlier in the year ('Level 2' and 'Twinnie') I just used two packs of dried CML Hell yeast per fermenter rather than go for a liquid starter, and they have been a couple of my best beers so far. I've tried a starter from dry yeast, and starters from liquid yeasts for lagers, and at the moment I'm pretty convinced by the pitch more packs of dry yeast approach - though perhaps tweak that with rehydration of dry yeast at 15, if pitching at 12 deg.

 

[foxbat]

Can someone tell me what they expect in terms of flavour from an underpitched lager yeast fermentation

Possibly more esters because they're produced during the growth phase, which will be more prolonged with an underpitch as the cells have to divide and multiply more to colonise the wort. It's questionable whether you'll taste it though.

The biggest danger with an extreme underpitch is that the yeast runs out of the oxygen it needs to multiply in the early phase before it's colonised the wort. In this scenario fermentation will stall.

 

[Thatscold]

While not the answer you're looking for, with a couple of my lagers earlier in the year ('Level 2' and 'Twinnie') I just used two packs of dried CML Hell yeast per fermenter rather than go for a liquid starter, and they have been a couple of my best beers so far. I've tried a starter from dry yeast, and starters from liquid yeasts for lagers, and at the moment I'm pretty convinced by the pitch more packs of dry yeast approach - though perhaps tweak that with rehydration of dry yeast at 15, if pitching at 12 deg.

This is exactly what I’ve been doing. I brew 42L batches and when I’ve looked at yeast calculators it’s suggested multi stage starters to get to the required cell count. CML Hell is cheap and 3 packs work for me at 20C (under pressure). That’s just over £5 on yeast. Cheaper than 1 pack of liquid yeast.

 

[The Furnace Green Brewer]

I have never used a yeast starter or re-hydrated the yeast, until last Tuesday, and the fermentation stopped short. I am going back to just sprinkling dry yeast into my aerated wort.

 

[An Ankoù]

I have never used a yeast starter or re-hydrated the yeast, until last Tuesday, and the fermentation stopped short. I am going back to just sprinkling dry yeast into my aerated wort.

It's most unlikely that your yeast stopping short has anything to do with the way you prepared the yeast. It's more Likely that the situation would have been even worse, otherwise. Done properly, both making a starter and rehydration can only improve the yeast culture and make it fitter to tackle the job in hand. On the other hand, if you're not sure about the processes or about the sanitation of the vessels, then you'd be better off pitching directly.

 

[The Furnace Green Brewer]

I have strict temperature control and did nothing different to any of my previous batches, I clean and sterilise my equipment, as I always do.

 

[Brewnaldo]

While not the answer you're looking for, with a couple of my lagers earlier in the year ('Level 2' and 'Twinnie') I just used two packs of dried CML Hell yeast per fermenter rather than go for a liquid starter, and they have been a couple of my best beers so far. I've tried a starter from dry yeast, and starters from liquid yeasts for lagers, and at the moment I'm pretty convinced by the pitch more packs of dry yeast approach - though perhaps tweak that with rehydration of dry yeast at 15, if pitching at 12 deg.

Aye, its really all about cell count in the end and dry yeast, which I use 90% of the time is certainly the easiest way to get there. I am a fan of CML Hell also, but this winter I hope to get my fermentation temp issues sorted and as such, lots more lager. Some I will pressure ferment warm (ish) and some at the proper temps for proper comparison. Also want to utilise the many fantastic sounding liquid lager strains available and ensure I do them justice. Messing with the calculators after reading some threads on here showed that my generic 1 litre starter for everything approach is pretty woeful

Possibly more esters because they're produced during the growth phase, which will be more prolonged with an underpitch as the cells have to divide and multiply more to colonise the wort. It's questionable whether you'll taste it though.

The biggest danger with an extreme underpitch is that the yeast runs out of the oxygen it needs to multiply in the early phase before it's colonised the wort. In this scenario fermentation will stall.

Ok. I dont think I have ever had an issue with stalls and lager, but I havent done many cold ferments with liquid yeast. Nevertheless, I have a five litre bottle with an airlock lid so no excuse not to step up to the proper cell counts and remove any doubt re flavours.

Cheers folks.