Well, I guess I stand corrected about the whole not refrigerating yeast starters thing. Apparently, this is a fairly common practice, much to my surprise. I’m still not at all sure that I see the point of doing it, as it seems to cause more problems than it solves, but if that’s what seems to work for you…[/quote]
The point of cooling a starter after fermentation is complete is to drop the yeast and get them as compact as possible. If you have a 2L starter (for example) and pitch it into a 5 gallon batch, you are essentially upping the total volume by 10% with spent wort to a fresh batch of beer. This wort/beer has most likely been skunked with oxygen and UV light. You don’t want to add a bunch of crappy beer to a nice fresh batch of wort.
And adding cold starter to cool wort isn’t a problem. Getting the yeast to wake up isn’t a “tricky” process. You pitch, they warm up and start eating.
This is very common practice.
Having said that, if I make a small starter where I already have enough yeast, but want to give it a jump start before pitching, I will pitch an active starter that’s maybe 500ml - 1L in size. Any thing bigger and I cool, decant, pitch.
Well, I guess I stand corrected about the whole not refrigerating yeast starters thing. Apparently, this is a fairly common practice, much to my surprise. I’m still not at all sure that I see the point of doing it, as it seems to cause more problems than it solves, but if that’s what seems to work for you…[/quote]
The point of cooling a starter after fermentation is complete is to drop the yeast and get them as compact as possible. If you have a 2L starter (for example) and pitch it into a 5 gallon batch, you are essentially upping the total volume by 10% with spent wort to a fresh batch of beer. This wort/beer has most likely been skunked with oxygen and UV light. You don’t want to add a bunch of crappy beer to a nice fresh batch of wort.
And adding cold starter to cool wort isn’t a problem. Getting the yeast to wake up isn’t a “tricky” process. You pitch, they warm up and start eating.
This is very common practice.
Having said that, if I make a small starter where I already have enough yeast, but want to give it a jump start before pitching, I will pitch an active starter that’s maybe 500ml - 1L in size. Any thing bigger and I cool, decant, pitch.[/quote]
I guess the real reason why this whole refrigeration thing strikes me as odd is because I’m in the custom of pitching the entire yeast starter, wort and all, into my fermenter. I do this because I typically only do 1 pint starters, so I’m not worried about the amount of liquid in it really affecting the total amount of wort in the fermenter to any serious degree, and because there’s actually still fermentable wort in the starter, so why waste it? Going to any real trouble to separate yeast from wort with such a small amount of liquid also seems to me to be a tedious and unnecessary chore, especially when my starter is composed of nothing more than water, dry malt extract, and maybe a little yeast nutrient, so there’s definitely nothing undesirable to filter out, either. But that’s just how I do it. Everybody has the right to do things their own way.
D1,
Your vision is clouded my man.
I just quick scanned through your last post and 1 pint starter even with a stirplate is next to useless and unless your starters are in high krausen always you will not have extract leftover in the wort. Even for “small” beers that hover around 1.040-1.050 I make at least 1L on a stirplate and “cool/crash” for just a brief period, say 1-5 hours during the actual brewday and then decant off the yeast cake and leave just enough wort to swirl up the cake and pitch pure yeast I do this even with a starter I want in high krausen to bottom line eliminate “waste” wort. Therefore as Dobe wrote your not adding problematic or high VDK wort to fresh wort or diluting. You can certainly do it your way but there are reasons its done like this. I work hard on my beer and want only slurry going into it, not wort that is “staled”/oxidized, contains high VDK etc…
Edit…Now on the other hand many have fermented their starters at the exact temps the main wort will reside at to prevent shock/other and in this case, sure then adding the wort will be fine if not stir plated as the wort saw no oxidation and will be low in overall VDK. But my thought is also that even if I dared consider this time consuming/ non necessary procedure then I am adding 1-3+L of extract wort to my all grain wort…Blexk, gasp THE HORROR! :mrgreen:
Don’t be too harsh on yourself, but taste a spent starter - yuk. You don’t want that in your beer. If you want to add new wort, do it after the wort has cooled.
I wouldn’t go so far as saying that a 1 pt starter is useless - if nothing else it will tell you that the yeast is alive and will get them into high gear so to speak - but it isn’t big enough to actually grow the cell count to any useful degree. If you are doing 5 gallon or larger batches and want to get the proper cell count for the pitch, you should almost always be using a larger starter. Mrmalty.com has some good articles on this topic:
If you want to get into the dirty details, Kai Troester has a great write-up of an experiment he did which shows how some of the extrapolations used to generate the Mr. Malty calculator could be corrected:
If you’re only making a 1 pint starter and keeping it at 70 degrees I hope you’re pitching it within about 12 hours or you are probably doing more harm than good to that yeast. Especially if you use a stir plate.
I make a starter to increase the amount of yeast I’m pitching. If I make a 1 liter starter, it may just get direct pitched into the wort after 18 hours on a stir plate. If it is a bigger starter or if I’m not ready for the yeast, into the fridge it goes to store and separate. Any starter that goes in the fridge comes out on brew day so I can pour off the beer it made and pitch just the slurry. Then it warms at room temp while I’m brewing.
It isn’t at all tricky to wake yeast back up in a large volume of liquid. If the liquid contains fermentables and is the right temp they’ll know what to do just fine.
[quote=“rebuiltcellars”]
If you want to get into the dirty details, Kai Troester has a great write-up of an experiment he did which shows how some of the extrapolations used to generate the Mr. Malty calculator could be corrected:
And if you use http://www.yeastcalc.com
instead of MrMalty, it gives you the option to use Kai’s formulas as well as Jamil’s. I also prefer http://www.yeastcalc.com
because it makes calculating multiple steps much easier.
[quote=“ITsPossible”]D1,
Your vision is clouded my man.
I just quick scanned through your last post and 1 pint starter even with a stirplate is next to useless and unless your starters are in high krausen always you will not have extract leftover in the wort. Even for “small” beers that hover around 1.040-1.050 I make at least 1L on a stirplate and “cool/crash” for just a brief period, say 1-5 hours during the actual brewday and then decant off the yeast cake and leave just enough wort to swirl up the cake and pitch pure yeast I do this even with a starter I want in high krausen to bottom line eliminate “waste” wort. Therefore as Dobe wrote your not adding problematic or high VDK wort to fresh wort or diluting. You can certainly do it your way but there are reasons its done like this. I work hard on my beer and want only slurry going into it, not wort that is “staled”/oxidized, contains high VDK etc…
Edit…Now on the other hand many have fermented their starters at the exact temps the main wort will reside at to prevent shock/other and in this case, sure then adding the wort will be fine if not stir plated as the wort saw no oxidation and will be low in overall VDK. But my thought is also that even if I dared consider this time consuming/ non necessary procedure then I am adding 1-3+L of extract wort to my all grain wort…Blexk, gasp THE HORROR! :mrgreen: [/quote]
I can see your point about avoiding problematic wort by dumping the leftover liquid in the starter, I guess, but I definitely don’t follow the rest. For one thing, the OG of the starter is the main point of importance, not the volume. Adding another pint of wort to a starter is not going to make a big difference unless you’re adding a large amount of yeast to it. One pint is perfectly sufficient for 1 vial of liquid yeast at an OG of 1.050 to 1.060 to get the yeast up and running and to get enough cells produced to ferment a 5 gallon batch. By adding another pint of liquid, all you’re really getting, besides a little bit more fermentable malt sugar, is more wort to have to separate from the yeast, as far as I can see. Besides, I don’t use a stir-plate, and a starter only needs less than 24 hours to fully ferment, so I’m not the least bit worried about oxygenated wort going into my fermenter. And if you don’t follow me on all of this, just look at Wyeast’s smack-pack starter package. Do they put an entire quart of liquid in those smack-packs? Certainly not, and if anyone would know what their own yeast needs in the way of a starter, it would definitely be them, right?
For another thing, there is no such thing as a brewers’ yeast that has a an attenuation rate of 100%, so yes, there will always be a small amount of unfermented sugar in any starter, no matter what you fed the yeast with, not that this a major issue. Anyway, I don’t mean to make an argument out of this. I’m just presenting some food for thought. I personally think that the whole “one quart starter’” thing is just some ballpark term somebody threw out into the thoughtosphere a long time ago in the early days of homebrewing, and the idea stuck even though it has no real solid scientific basis.The bottom line, for me, is that I don’t have problems with fermentation when I only use one pint of liquid for a starter, and that’s all I need to know.
The point of the starter (for most of us I think), is to pitch the proper amount of yeast into our wort. This means increases the number of yeast, not just getting the yeast a quick workout prior to pitching. To do this you need to have enough fermentable liquid… 1 pint ain’t cutting it for all 5 gallon batches, because all 5 gallon batches are not created equal. http://www.wyeastlab.com/hb_pitchrate.cfm
The point of the starter (for most of us I think), is to pitch the proper amount of yeast into our wort. This means increases the number of yeast, not just getting the yeast a quick workout prior to pitching. To do this you need to have enough fermentable liquid… 1 pint ain’t cutting it for all 5 gallon batches, because all 5 gallon batches are not created equal. http://www.wyeastlab.com/hb_pitchrate.cfm
That was an excellently composed and informative post, but where are the links you mention regarding the scientific thoughtosphere? Or are you just referring to the links you posted about Wyeast’s products?
I’ve never heard of anybody refrigerating a yeast starter. What’s the point? Why can’t the starter stay at room temp, just like a regular fermenter? Don’t you think that the cooling and warming process adds unnecessary complexity and potential problems to the process? I’m confused.[/quote]
Most people cold crash their starters so as not to add all the spent wort into their fermentation which was mentioned above by others. Even so, White Labs has stated it’s beneficial to cold crash starters for yeast to build up certain key nutrient reserves that help them perform better in fermentation.
From Wyeast (as you stated, they would know)
Starter Recipe:
The optimal media for cell growth and health require using a malt based media (DME) fortified with nutrients. Gravity should be kept near 1.040 and cultures should be grown at 70°F.
Recipe
0.5 cup DME (100g, 3.5oz)
½ tsp Wyeast Nutrient 1qt.(1L) H2O
Mix DME, nutrient, and water.
Boil 20 minutes to sterilize.
Pour into a sanitized flask or jar with loose lid or foil.
Allow to cool to 70°F.
Shake well and add yeast culture.
