Help Understanding Yeast Starters

Background: I have brewing now for about 2 years; made the switch over to all grain about 6 months ago.

I have done some reading, though it has been a while now so I should go back and reread, but I seem to recall that making larger starter batches for bigger beers should utilize the same stuffs that will be going into the beer. Doing this will make it so that the yeasties are acclimated to the conditions that you will be pitchign them into and thus they will not need to change their structural make-up to accomodate a new environment - i.e. they will just be able to get right down to business rather than wasting time and energy to acclimate.

Question: So I am wondering how the yeast starters work. Should I calculate a tiny batch of the brew that I will be doing and:

1) run that through, making let's say a 1 gallon batch
2) then pitch a single pack (be it dry or wet) into that and let it go for a few
days
3) force chill it to calm the yeasties down
4) then drain off the excess liquid, bring the temp back up to the temp of the
big batch and pitch that

That seems like a lot of work, albeit fun and interesting, to get a larger batch of yeast.

Thanks in advance!!

P.S.: I'm running a Dbl Chocolate Stout, then a Wit, and then Vanilla Bourbon Porter.....which will all be in my newly built (90% complete) 8 keg keezer The liver is gonna need to work overtime this spring!

I am absolutely no expert on the subject, but this is what I understand:

Make the starter wort out of w/e malt you want, most people prefer DME because of its availability, storability and ease of use. Starter size can be calculated by the mrmalty calculator, I throw caution to the wind and just use a 1L starter every time. Pitch your store bought yeast, I just use one vile/pack for whatever size I am doing. After 24 hours you should be at the yeast count you are looking for. You can pitch as is, or chill it to drop the yeast out of suspension. This is done so that you can decant the majority of the liquid for the starter as to not add it to your beer.

I usually start a day or three before I brew. Typically make the starter on Thursday, brew on Saturday.

You don't need to approximate the beer you plan on making. Just use any DME. I'd say most people just use light DME. The important thing is that you have the yeast eating the same type of sugar that you will have in your beer. This is predominantly maltose, which is what you will get in DME. You just don't want to make the starter out of something like table sugar/brown sugar/honey/maple syrup, because those things will not consist of maltose.

I did find the Mr Malty site and that is definitely a good start. I can see what your saying about the sugar types and that makes sense. I think that is what I'll run with then, a light DME solution at whatever MR Malty suggests.

Kord78 said:

I did find the Mr Malty site and that is definitely a good start. I can see what your saying about the sugar types and that makes sense. I think that is what I'll run with then, a light DME solution at whatever MR Malty suggests.

Click to expand...

That calculator has never done me wrong. Always nice, fast, active ferments.

I use Mr Malty all the time...

- I make a small wort of ~1040 from DME according to the Mr Malty calculator (add the right amount of DME/water for the size starter I need). Make sure you select the proper drop down selection for what you're gonna do (stirplate, occasional shaking, leave it alone).
- I pour into my flask and chill to pitching temps.
- I pitch the requisite number of vials (I make bigger starters to reduce the # of vials I need to buy - cheap).
- I use a stir plate so I put the starter on the stir plate, turn it on and cover it with foil.
- ~24 hours later, I cold crash for however much time I need in order to decant off as much of the clear liquid as I can.
- shake to get the yeast broken up and pitch into your chilled wort.

ThePearsonFam said:

- I make a small wort of ~1040 from DME according to the Mr Malty calculator (add the right amount of DME/water for the size starter I need).

Click to expand...

This is pretty much common knowledge, but the ratio of DME to water for a ~1.040 starter is 1:10. In other words, for a 1000 ml (1 L) starter, you would use 100 grams of DME (Extra light DME is the best choice). You can scale up from there.

The correct way to do it is to measure 100 grams of DME in your flask, then top off water until you reach the 1000 ml mark, but since my starter begins in a sauce pan (easier to break up clumps and makes boil overs a non-issue), I weigh 100 grams in the pan, measure 1000 ml in the flask, then just pour the water into the pan and get it up to a boil. Close enough. Then I dump it through a funnel and into a flask for the full 15 minute boil.

A couple other adders...
First, starters are only for liquid yeasts. Second, it will not hurt to add 1/4 tsp or so of yeast nutrient to the starter wort. Also, as mentioned, a stir plate is worth it's weight in gold. I do not see this mentioned too often, but hops do not go into your starter. Finally, no airlock! Just sanitize a square of aluminum foil and wrap it loosely over the top of the flask. It is my practice to pitch the entire starter into my wort. 1 liter is not going to make a dramatic difference to your 5 Gallons of wort. If I had a 1 gallon starter going into a light lager, I might feel differently.

Joe

jfowler1 said:

Finally, no airlock!

Click to expand...

Why no airlock? I always put an airlock on mine, just because...

I assume no airlock because you want the liquid to continue to oxygenate whilst they little guys are working themselves up?

Last night i had to go get 1/4" tubing so I picked up a stirr...er thingy and am now going to investigate stir plates. I still have a few days before the keezer is done and I'm ready to brew again.

Kord78 said:

I assume no airlock because you want the liquid to continue to oxygenate whilst they little guys are working themselves up?

Click to expand...

That is it in a nut shell.

You want to promote a free exchange of gases while the starter is on a stir plate. You WANT air to be pulled down against the starter wort while the little stir bar is creating a vortex. An airlock creates a blanket of CO2, which is not really what you are going for here. I guess you can think of a starter on a stir plate like 24 hours of aeration through an air pump....it is serving a very similar function. "No stir plate" can be remedied by simply giving the flask a good swirl whenever you walk by it. And don't sweat the lack of an airlock on the sanitation side. Airborn nasties can't navigate up under the foil and down into the starter.

There is a misconception that starters are for yeast growth; they are more about yeast health. Growth is almost a secondary bi-product.

Health first; growth second.

Joe

What I do for big beers - not sure it's optimal - is pitch the smack pack into 1.5L of 1.040 malt extract wort. Stirplate until krausen falls, then chill overnight. Make another wort, same size and gravity and cool to pitching temp. Decant spent wort, add fresh wort, stir again until krausen falls. Chill, decant, and pitch. I can get ~250 mL of thick slurry this way.

I also use this technique to propagate yeast for storage. 2nd iteration slurry goes into 4-6 pressure-cooked small canning jars. Refrigerate until needed. When used, repropagate from the jar as above.

Something I don't read about often enough...

If possible, try to have 2/3 and at minimum 50% headspace in the starter vessel. A homebrewer who works as a micro-biologist told me this. It's needed for proper gas exchange. I started paying attention to yeast labs at breweries and on TV and I noticed the same. I used to cram my starters into a standard 1/2 gal. growler. Now I use a 1.5 gallon vino jug and the yeast growth is noticeably better, even with the stir plate.

SickTransitMundus said:

What I do for big beers - not sure it's optimal - is pitch the smack pack into 1.5L of 1.040 malt extract wort. Stirplate until krausen falls, then chill overnight. Make another wort, same size and gravity and cool to pitching temp. Decant spent wort, add fresh wort, stir again until krausen falls. Chill, decant, and pitch. I can get ~250 mL of thick slurry this way.

I also use this technique to propagate yeast for storage. 2nd iteration slurry goes into 4-6 pressure-cooked small canning jars. Refrigerate until needed. When used, repropagate from the jar as above.

Click to expand...

I do three 2L iterations of this for my lagers. 7-8 hour lagtimes @ 50F. The last step up is always a PITA to get the bar spinning in that much yeast!

The OP also seems to be asking if you make bigger starters for big beers - this isn't recommended. 1.040 gravity for all starters. It's more important to grow healthy yeast than any sort of acclimatization.

I brew all grain and I found it's convenient to make extra on the day I brew and boil the extra separate from the beer, meaning no hops. This can be siphoned off the hot break and then canned in a pressure cooker.

I can keep quarts of sterile wort on the shelf and when I want to make a starter, I just pop one open and I'm good to go! It's a bit more work than maybe using DME, but you only do it 1 time and you have plenty of ready-to-use wort.

You could do the same thing with DME. Make a big batch of it and can it for later use.

Also, when making smaller ales, I just make up a regular starter and pitch the whole thing in at high krausen. For bigger beers, or Lagers, it's a good idea to chill the starter and pour off the clear liquid. There will be much more of that stuff and it can change the batch of beer. For smaller ales, it's probably not going to affect the outcome.

jfowler1 said:

This is pretty much common knowledge, but the ratio of DME to water for a ~1.040 starter is 1:10. In other words, for a 1000 ml (1 L) starter, you would use 100 grams of DME (Extra light DME is the best choice). You can scale up from there.

The correct way to do it is to measure 100 grams of DME in your flask, then top off water until you reach the 1000 ml mark, but since my starter begins in a sauce pan (easier to break up clumps and makes boil overs a non-issue), I weigh 100 grams in the pan, measure 1000 ml in the flask, then just pour the water into the pan and get it up to a boil. Close enough. Then I dump it through a funnel and into a flask for the full 15 minute boil.

A couple other adders...
First, starters are only for liquid yeasts. Second, it will not hurt to add 1/4 tsp or so of yeast nutrient to the starter wort. Also, as mentioned, a stir plate is worth it's weight in gold. I do not see this mentioned too often, but hops do not go into your starter. Finally, no airlock! Just sanitize a square of aluminum foil and wrap it loosely over the top of the flask. It is my practice to pitch the entire starter into my wort. 1 liter is not going to make a dramatic difference to your 5 Gallons of wort. If I had a 1 gallon starter going into a light lager, I might feel differently.

Joe

Click to expand...

i thought the 10:1 ratio is after accounting for boil off etc?

terrapinj said:

i thought the 10:1 ratio is after accounting for boil off etc?

Click to expand...

from http://www.mrmalty.com/starter_faq.htm

"When making starter wort, keep the starting gravity between 1.030 and 1.040 (7 - 10°P). You do not want to make a high gravity starter to grow yeast. As a ballpark measurement, use about 6 ounces (by weight) of DME to 2 quarts of water. If you're working in metric, it couldn't be easier. Use a 10 to 1 ratio. Add 1 gram of DME for every 10 ml of final volume. (If you're making a 2 liter starter, add water to 200 grams of DME until you have 2 liters total.) Add ¼ teaspoon of yeast nutrient, boil 15 minutes, cool, and add yeast."

I read that as 10:1 pre-boil (which is a rule I do not even follow myself). I would be adding 2000 ml of water to 200 grams of DME, which I guess would be less concentrated than a total volume. It is one less transfer for me, and it is a little tough to pour dme into a flask, so I just cheat a little, as I noted earlier.

jfowler1 said:

from http://www.mrmalty.com/starter_faq.htm

"When making starter wort, keep the starting gravity between 1.030 and 1.040 (7 - 10°P). You do not want to make a high gravity starter to grow yeast. As a ballpark measurement, use about 6 ounces (by weight) of DME to 2 quarts of water. If you're working in metric, it couldn't be easier. Use a 10 to 1 ratio. Add 1 gram of DME for every 10 ml of final volume. (If you're making a 2 liter starter, add water to 200 grams of DME until you have 2 liters total.) Add ¼ teaspoon of yeast nutrient, boil 15 minutes, cool, and add yeast."

I read that as 10:1 pre-boil (which is a rule I do not even follow myself). I would be adding 2000 ml of water to 200 grams of DME, which I guess would be less concentrated than a total volume. It is one less transfer for me, and it is a little tough to pour dme into a flask, so I just cheat a little, as I noted earlier.

Click to expand...

Can you argue against yourself?

Add 1 gram of DME for every 10 ml of final volume.

I don't know.....I'd say 10:1 pre-boil / post-boil; it's close enough.

thanks for the link - i knew i had read post boil somewhere - guess i missed the next sentence

i guess since its a range of OG between 1.030 - 1.040 its not too crucial to end with exactly 10ml:1g in the flask when you pitch

Homercidal said:

I brew all grain and I found it's convenient to make extra on the day I brew and boil the extra separate from the beer, meaning no hops. This can be siphoned off the hot break and then canned in a pressure cooker.

I can keep quarts of sterile wort on the shelf and when I want to make a starter, I just pop one open and I'm good to go! It's a bit more work than maybe using DME, but you only do it 1 time and you have plenty of ready-to-use wort.

You could do the same thing with DME. Make a big batch of it and can it for later use.

Also, when making smaller ales, I just make up a regular starter and pitch the whole thing in at high krausen. For bigger beers, or Lagers, it's a good idea to chill the starter and pour off the clear liquid. There will be much more of that stuff and it can change the batch of beer. For smaller ales, it's probably not going to affect the outcome.

Click to expand...

Homercidal - that is a really good idea!! I thought about it for a moment and it occurred to me that my initial statement of "matching the start fluid to the wort in order to have the yeasties in the correct environment" would have that fit in perfectly! That one is going into the book of things to remember...since my brain is fried and I can't remember things.........now where is that book

So, I am currently in the process of building my stir plate and have learned the following lesson:

When the threads say to use a power supply fan, they mean it. I initially tried to use a CPU fan, however, it just pulses rather than runs. This has somethign to do with the extra two wires I'm sure (fan speed sensor and pulse-width modulation controller). So now I am back to a power supply fan, but it does not have the same power as the CPU fan did so I am unsure of how it will come out.

Side note: I just picked up a 2.7 cu-ft mini-fridge ($35 at a tag sale) in order to make a temperature controlled environment for my stir plate - yep, I'm a tinkerer

Lastly: I am running into issues with my keezer and Ranco temp controller. I will be posting that in the proper forum, so anyone following this thread that might be able to impart some wisdom - it would be greatly appreciated.

To all: I am enjoying the discussion here and will be putting it to good use soon Thanks all! Great community!!

jfowler1 said:

That is it in a nut shell.

You want to promote a free exchange of gases while the starter is on a stir plate. You WANT air to be pulled down against the starter wort while the little stir bar is creating a vortex. An airlock creates a blanket of CO2, which is not really what you are going for here. I guess you can think of a starter on a stir plate like 24 hours of aeration through an air pump....it is serving a very similar function. "No stir plate" can be remedied by simply giving the flask a good swirl whenever you walk by it. And don't sweat the lack of an airlock on the sanitation side. Airborn nasties can't navigate up under the foil and down into the starter.

There is a misconception that starters are for yeast growth; they are more about yeast health. Growth is almost a secondary bi-product.

Health first; growth second.

Joe

Click to expand...

Thats all well and good, but since co2 is heavier than air, how much actually gets in? especially if the yeast is constantly producing it, it seems like the overall flow would be out of the flask, not in...

This is one of my pet peeves when it comes to homebrewing lore - yes, CO2 is heavier than air if you separately compare the gases. But there is CO2 in air. And they mix.

CO2 and air is not like oil and water - it's like mixing two worts of different gravities. You get a little mixing, a little stratification, but it's not a clear line of division.