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General Category => Yeast and Fermentation => Topic started by: jivetyrant on February 13, 2011, 02:04:35 PM

Title: My first yeast starter - questions!
Post by: jivetyrant on February 13, 2011, 02:04:35 PM
So I'm planning on doing an Imperial Stout today, target ABV of 10.7% with an OG of 1.104, FG 1.024.  It was recommended that I use some more advanced brewing techniques than I have tried previously, including preparing a yeast starter.  The gentleman at my local homebrew supply store told me that the best way to prepare a starter is to combine about 4 cups of water with 1 cup of DME, boil for 10-15 minutes and cool to pitching temp. (75ish)  Add 1/8 tsp of yeast nutrient and pitch my yeast, in this case 1 vial of WLP001, white labs california ale then shake thoroughly to aerate.  The gear he recommended was a 2000ml flask and a foam stopper, both of which I purchased.  His last piece of advice was to give it a quick shake several times a day to keep the yeast in suspension as it would promote more rapid metabolism of the sugars in the starter.  He told me to prep it a day or two ahead of time and to pour off and clear liquid that formed on top of the starter as I would not want it in my carboy.

Well, I followed his advice to the letter but my starter isn't doing a hell of a lot!  it's got a thin layer of bubbles but isn't as vigorous as I would have expected.  I started it yesterday at about 11am, I'm planning on brewing tonight at about 5pm, perhaps earlier if possible.  Is my timeline realistic?  Was my starter prepared correctly?  Am I just expecting more activity from my starter than is normal?  Halp!
Title: Re: My first yeast starter - questions!
Post by: majorvices on February 13, 2011, 02:18:59 PM
You don't always get a lot of foam on a yeast starter. Just keep swirling it every chance you get and don't worry.

FWIW you are doing great by making a starter, but really, you will have better beer making a starter for every beer, not just high gravity. Go with what you have today, but next time consult http://www.mrmalty.com/calc/calc.html to see exactly how big a starter you need for every batch.
Title: Re: My first yeast starter - questions!
Post by: jivetyrant on February 13, 2011, 02:47:00 PM
Wow, that's a damn handy tool you've got there!  Very cool stuff. :)
Title: Re: My first yeast starter - questions!
Post by: denny on February 13, 2011, 03:10:50 PM
If you're not using a stir plate, I'd recommend making your starter at least 3-4 days in advance. 
Title: Re: My first yeast starter - questions!
Post by: jivetyrant on February 13, 2011, 03:22:30 PM
I was afraid of that, guess I'm not brewing today :p
Title: Re: My first yeast starter - questions!
Post by: Hokerer on February 13, 2011, 04:45:39 PM
And, for a 1.104 OG, you're going to want a bigger starter than just one quart.
Title: Re: My first yeast starter - questions!
Post by: jivetyrant on February 13, 2011, 05:17:09 PM
should I boil and cool more water then just add it to the existing starter?  How much?

Should I also use more DME?  How much?

Should I spring for another vial of yeast?
Title: Re: My first yeast starter - questions!
Post by: denny on February 13, 2011, 05:32:39 PM
should I boil and cool more water then just add it to the existing starter?  How much?

Should I also use more DME?  How much?

Should I spring for another vial of yeast?

You need to use both more DME and more water.  More yeast will be helpful, too.  For the definitive answers, though, please see mrmalty.com.
Title: Re: My first yeast starter - questions!
Post by: punatic on February 13, 2011, 11:38:12 PM
prepare a starter is to combine about 4 cups of water with 1 cup of DME, boil for 10-15 minutes and cool to pitching temp.

Well, I followed his advice to the letter but my starter isn't doing a hell of a lot! 

4 cups of water plus 1 cup of DME gave your starter wort a original gravity of 1.120 
BEFORE you boiled it.
Boiling removed water and increased the original gravity of the starter wort even higher.

I suspect your starter yeast is suffering from high gravity shock.
Title: Re: My first yeast starter - questions!
Post by: majorvices on February 14, 2011, 01:06:00 AM
10-12 oz of DME to 1 gallon or 4L of water will give you between 1.030 and 1.040 OG starter. For a 2L or 1/2 gallon starter use 5-6oz DME. That's what is easiest for me to remember.  You definitely don't want the starter stronger than 1.040 or so. You want to grow yeast, not scare the hell out of them, and high gravity worts cause lots of stress. In layman's terms its like having a nice salad as opposed to being involved in a hotdog eating contest.  ;)
Title: Re: My first yeast starter - questions!
Post by: tschmidlin on February 14, 2011, 01:30:40 AM
prepare a starter is to combine about 4 cups of water with 1 cup of DME, boil for 10-15 minutes and cool to pitching temp.

Well, I followed his advice to the letter but my starter isn't doing a hell of a lot!

4 cups of water plus 1 cup of DME gave your starter wort a original gravity of 1.120 
BEFORE you boiled it.
Boiling removed water and increased the original gravity of the starter wort even higher.

I suspect your starter yeast is suffering from high gravity shock.
What numbers are you using to calculate this?  Working backwards, it looks like you're estimating a cup of DME to weight 11 oz or the water volume is off by half.  Granulated sugar is closer to 7 oz, in my experience a cup of DME is less, about 5.5 - 6 oz (there's variability).  I figure this starter would be about 1.065 pre-boil, more after.  It's still too high though.  A half cup of DME in a quart would be better for the starter.

But weighing is better than volume measurements, I use DME equaling 8-10% of the water weight.
Title: Re: My first yeast starter - questions!
Post by: punatic on February 14, 2011, 02:10:42 AM

prepare a starter is to combine about 4 cups of water with 1 cup of DME, boil for 10-15 minutes and cool to pitching temp.

Well, I followed his advice to the letter but my starter isn't doing a hell of a lot!

4 cups of water plus 1 cup of DME gave your starter wort a original gravity of 1.120 
BEFORE you boiled it.
Boiling removed water and increased the original gravity of the starter wort even higher.

I suspect your starter yeast is suffering from high gravity shock.
What numbers are you using to calculate this?  Working backwards, it looks like you're estimating a cup of DME to weight 11 oz or the water volume is off by half.  Granulated sugar is closer to 7 oz, in my experience a cup of DME is less, about 5.5 - 6 oz (there's variability).  I figure this starter would be about 1.065 pre-boil, more after.  It's still too high though.  A half cup of DME in a quart would be better for the starter.

But weighing is better than volume measurements, I use DME equaling 8-10% of the water weight.

Pre-boil Specific Gravity calculations:

Densities measured at STP
Water has a density of 1.000 g/mL
DME has a density of 1.6 g/mL
1 cup = 8 fluid oz.
1 fluid ounce = 29.57 mL

1 cup DME = 1cup x 8oz/cup x 29.57mL/oz x 1.6g/mL = 378.5g DME 

4 cups water = 4cup x 8oz/cup x 29.57mL/oz x 1.0g/mL = 946.2g water

5 cups solution = 378.5g DME + 946.2g water = 1324.7g wort

5 cups solution = 5 cups x 8oz/cup x 29.57mL/oz = 1182.8 mL wort

Density = 1324.7g / 1182.8mL = 1.120g/mL

Specific Gravity = (1.120g/mL) / (1.000g/mL) = 1.120

Title: Re: My first yeast starter - questions!
Post by: jivetyrant on February 14, 2011, 02:18:34 AM
I have another question!

My starter is no longer producing much in the way of bubbles and there is a yeast cake that has formed in the bottom of the flask.  Shaking the flask yields much less vigorous foaming than before and the yeast cake does not break up fully, it looks somewhat chunky now.  Does this mean that my starter is "done," so to speak?  If so, how can I store it until I'm ready to brew? (probably in the next couple of days)  Can I just stash it in the fridge and take it out 4 or so hours before brewing, or am I now on a timeline before it goes south?
Title: Re: My first yeast starter - questions!
Post by: Hokerer on February 14, 2011, 03:13:07 AM
Stashing it in the fridge is the right thing to do.  It also has the added advantage that, shortly before you're ready to use it, you can decant off the spent "beer" and just pitch the yeast.  The time in the fridge gets the yeast to settle to the bottom.
Title: Re: My first yeast starter - questions!
Post by: punatic on February 14, 2011, 03:18:59 AM
I think the sediment you are seeing is mostly trub.  Yeast sediment tends to be "dusty" when disturbed.  The yeast often appears as a thin layer of lighter colored sediment on top of the darker trub sediment on the bottom of the fermentation vessel.

If it were me, I would make a new yeast starter from scratch, using 100g of DME to 1 liter of water (1/4 cup DME to 1 quart of water) and pitch a new yeast culture.  
Or better still 1/2 cup DME to 1/2 gallon of water.

IMHO - Replacing a starter is less expensive than replacing a batch of beer that has off-flavors.

If you should decide to use what you have, storing it in a dark, room-temperature place for a day or two is good.  Storing it in the fridge will cause a longer lag time when you pitch it into the wort.  For more than a day or two - the fridge is the way to go.
Title: Re: My first yeast starter - questions!
Post by: maxieboy on February 14, 2011, 04:08:19 AM
  Storing it in the fridge will cause a longer lag time when you pitch it into the wort. 

Could you expand on this? Myself and lots of excellent homebrewers have followed numerous commercial breweries lead of pitching cold.
Title: Re: My first yeast starter - questions!
Post by: a10t2 on February 14, 2011, 04:28:37 AM
1 cup DME = 1cup x 8oz/cup x 29.57mL/oz x 1.6g/mL = 378.5g DME

Obviously there's a lot of variability, but a cup of DME is ~150 g.
Title: Re: My first yeast starter - questions!
Post by: tygo on February 14, 2011, 04:45:06 AM
If it were me, I would make a new yeast starter from scratch, using 100g of DME to 1 liter of water

Good advice  ;)

If you should decide to use what you have, storing it in a dark, room-temperature place for a day or two is good.  Storing it in the fridge will cause a longer lag time when you pitch it into the wort.  For more than a day or two - the fridge is the way to go.

I always chill my starters down in the fridge.  I haven't had any problems with lag time thus far.
Title: Re: My first yeast starter - questions!
Post by: maxieboy on February 14, 2011, 04:45:43 AM
1 cup DME = 1cup x 8oz/cup x 29.57mL/oz x 1.6g/mL = 378.5g DME

Obviously there's a lot of variability, but a cup of DME is ~150 g.

It appears that it's just not his day... ;)
Title: Re: My first yeast starter - questions!
Post by: maxieboy on February 14, 2011, 04:49:03 AM
I always chill my starters down in the fridge.  I haven't had any problems with lag time thus far.

+1
Title: Re: My first yeast starter - questions!
Post by: punatic on February 14, 2011, 05:04:31 AM
1 cup DME = 1cup x 8oz/cup x 29.57mL/oz x 1.6g/mL = 378.5g DME

Obviously there's a lot of variability, but a cup of DME is ~150 g.

It appears that it's just not his day... ;)

Hey you guys liked the 1.6g/mL for DME  figure just fine when I used it here:
How Do you Make a Yeast Starter? (http://www.homebrewersassociation.org/forum/index.php?topic=5929.msg71052#msg71052)

Also, 1 cup of water weighs 236.7g 
1cup x 8oz/cup x 29.57mL/oz x 1g/mL = 236.7g

So you're saying your cup of DME only weighs 2/3 as much as cup of water?
If I were you I'd take that DME back to the store and get a refund.   ::)
Title: Re: My first yeast starter - questions!
Post by: maxieboy on February 14, 2011, 05:43:56 AM
 A cup of DME does not weigh 378.5g(13.35oz!). You won't convince anyone of that. Depending on brand and how you measure a cup, 4.5oz-6.5oz at the most.
Title: Re: My first yeast starter - questions!
Post by: morticaixavier on February 14, 2011, 06:32:39 AM
1 cup DME = 1cup x 8oz/cup x 29.57mL/oz x 1.6g/mL = 378.5g DME

Obviously there's a lot of variability, but a cup of DME is ~150 g.

It appears that it's just not his day... ;)

Hey you guys liked the 1.6g/mL for DME  figure just fine when I used it here:
How Do you Make a Yeast Starter? (http://www.homebrewersassociation.org/forum/index.php?topic=5929.msg71052#msg71052)

Also, 1 cup of water weighs 236.7g 
1cup x 8oz/cup x 29.57mL/oz x 1g/mL = 236.7g

So you're saying your cup of DME only weighs 2/3 as much as cup of water?
If I were you I'd take that DME back to the store and get a refund.   ::)


Are you thinking of LME? Liquid Malt Extract? Dry malt extract is very light compared to water. as not particularly easy to measure by volume (fl oz) as the amount of moisture in the air will greatly affect the weight as will how tightly packed the cup is.
Title: Re: My first yeast starter - questions!
Post by: tschmidlin on February 14, 2011, 06:34:57 AM
DME has a density of 1.6 g/mL
1 cup = 8 fluid oz.
1 fluid ounce = 29.57 mL

1 cup DME = 1cup x 8oz/cup x 29.57mL/oz x 1.6g/mL = 378.5g DME  
Fair enough, but that cup of DME is not full of 100% DME, it has quite a bit of air.  A cup of DME measured from a bag of powdered DME will weigh about half of that.
Title: Re: My first yeast starter - questions!
Post by: punatic on February 14, 2011, 07:56:39 AM
OK - rule of thumb 1 lb of DME added to 1 gallon of water will give you a specific gravity of 1.045 (http://morebeer.com/search/103553/beerwinecoffee/coffeewinebeer/Dry_Malt_Extract)

1 lb DME = 1 lb
1 gal water = 8.34 lb
1 lb DME + 1gal water = 9.34 lb

9.34 lb / Vwort = 1.045 x (8.34 lb/gallon)
9.34 lb/ Vwort = 8.715 lb/gallon
9.34lb / (8.715 lb/gallon) = Vwort = 1.072 gallon
Vdme = Vwort - Vwater
Vdme = 1.072 gallon - 1.000 gallon = 0.072 gallon
density of DME = 1 lb / 0.072 gallons = 13.89 lb/gallon
(13.89 lb/gallon) x (1 gallon / 16cup ) x (16 wt.oz / 1 lb) = 13.89 wt.oz. / cup
Specific Gravity of DME = (13.89 lb/gallon) / (8.34lb/gallon) = 1.665

Recall - Specific gravity can be expressed as g/mL 
therefore DME density = 1.665 g/mL
More dense than the 1.6 g/mL I used in my previous calculations
Title: Re: My first yeast starter - questions!
Post by: tygo on February 14, 2011, 12:15:17 PM
It's a little early in the morning for me to follow math.  But I can scoop a cup of DME out of the bag and put it on a scale.  185 grams.  Munton's Extra Light DME, full cup, packed down somewhat.
Title: Re: My first yeast starter - questions!
Post by: a10t2 on February 14, 2011, 03:37:59 PM
OK - rule of thumb 1 lb of DME added to 1 gallon of water will give you a specific gravity of 1.045 (http://morebeer.com/search/103553/beerwinecoffee/coffeewinebeer/Dry_Malt_Extract)

Actually, that isn't quite right either. One pound of DME made into a solution with a *total volume* of one gallon will have an SG of around 1.045. You're also assuming that the volume of the solution is equal to the sum of the volumes of the solute and solvent, which is a notoriously common fallacy in chemistry.

Using the density of a solid's constituent particles introduces a lot of error when that solid is granular. The packing fraction will make a huge difference. The variation between sifted and packed flour, for example, is 25%: http://www.cookingforengineers.com/article/63/Wheat-Flour That's why people are always encouraged to measure by mass rather than volume.

Notice that you're saying a gallon of DME weighs about 14 lb. I'm sure you've seen a 5 lb bag of DME at a LHBS or elsewhere. Does it have a volume of 1/3 gal, or is it more like a gallon?
Title: Re: My first yeast starter - questions!
Post by: punatic on February 14, 2011, 04:10:51 PM
Alright.!  Some of you are getting close.

A hint:
bulk density vs particle density...
Title: Re: My first yeast starter - questions!
Post by: denny on February 14, 2011, 04:14:49 PM
Storing it in the fridge will cause a longer lag time when you pitch it into the wort.

Certainly not in my experience.  I took a slurry out of the fridge yesterday and within 10 min. I pitched it, before it could warm up.  I had fermentation going within 2 hours.
Title: Re: My first yeast starter - questions!
Post by: maxieboy on February 14, 2011, 04:34:10 PM
Alright.!  Some of you are getting close.

A hint:
bulk density vs particle density...

 ::)
 I'm no mathmagician or scientist, but you don't need to be to figure out the DME volume and weight issue.
We're still waiting on the cold pitching lag time theory...
Macros, micros and brewpubs are doing it and they have the most to lose if something goes wrong due to increased lag times.
Title: Re: My first yeast starter - questions!
Post by: bluesman on February 14, 2011, 04:38:06 PM
I like to prepare starters with DME and water to a S.G.=1.020-1.030.

I use approximately .75lb DME to 1 gallon of water which will make approx 30GU's or 1.030 after boiling for 10 min. This ratio of DME to water seems to give me the best results.

I then chill the starter wort down to the mid 60's and pitch a vial, smack pack or about 2-3 Tbsp slurry and put on a stir plate for a few days. The starter wort is then cold crashed to drop out all of the yeast into a cake on the bottom of the flask or container.

When I'm ready to pitch the yeast into my beer wort, I'll remove the starter from the refrigerator several hours prior to pitching and decant the spent wort and only pitch the yeast cake.

Title: Re: My first yeast starter - questions!
Post by: morticaixavier on February 14, 2011, 05:03:09 PM
All this talk about starters and cold crashing brings up a question for me. If you are doing a starter for a hefeweizen wouldn't cold crashing and decanting select for the more floculant yeasts? thus causing your hefe to be to clear? (mitout hefe instead of mit?)
Title: Re: My first yeast starter - questions!
Post by: punatic on February 14, 2011, 05:05:21 PM

 ::)
 I'm no mathmagician or scientist, but you don't need to be to figure out the DME volume and weight issue.
We're still waiting on the cold pitching lag time theory...
Macros, micros and brewpubs are doing it and they have the most to lose if something goes wrong due to increased lag times.

Lobbying to be a moderator perhaps?
Title: Re: My first yeast starter - questions!
Post by: maxieboy on February 14, 2011, 05:51:42 PM
Lobbying to be a moderator perhaps?

lol, no. It has never crossed my mind.
Title: Re: My first yeast starter - questions!
Post by: tschmidlin on February 14, 2011, 08:28:47 PM
Alright.!  Some of you are getting close.

A hint:
bulk density vs particle density...
Are you seriously going to pretend that you're trying to teach us something? :o ;D  Admit it, you neglected to account for the air when you scoop a cup of DME! ;D

I don't know what you mean by "getting close", I said it:
Fair enough, but that cup of DME is not full of 100% DME, it has quite a bit of air.  A cup of DME measured from a bag of powdered DME will weigh about half of that.

Morticai said it:
how tightly packed the cup is.

Sean said it:
Using the density of a solid's constituent particles introduces a lot of error when that solid is granular. The packing fraction will make a huge difference. The variation between sifted and packed flour, for example, is 25%: http://www.cookingforengineers.com/article/63/Wheat-Flour That's why people are always encouraged to measure by mass rather than volume.

Do you have some magical phrase that you are looking for?
Title: Re: My first yeast starter - questions!
Post by: punatic on February 15, 2011, 02:46:01 AM
I don't know...how about:
As porosity goes to 0, bulk density approaches particle density.


Hey, the boards were a bit slow this morning, so I figured I'd stir it up a bit...   ;)

So BFI is the only one allowed to have fun sometimes?

You're good with 1 cup DME to 4 cups water?

Never mind.
Title: Re: My first yeast starter - questions!
Post by: punatic on February 15, 2011, 03:12:37 AM
Lobbying to be a moderator perhaps?

lol, no. It has never crossed my mind.

Oh man... you edited out the altruistic stuff. 
No worries, I wasn't offended.  :)
Title: Re: My first yeast starter - questions!
Post by: tschmidlin on February 15, 2011, 05:56:22 AM
I don't know...how about:
As porosity goes to 0, bulk density approaches particle density.
;D  That works.  I don't remember that phrase from any of my classes, but that could be because they were mechanical engineering or biochemistry classes, not civil engineering or materials science or soil or any of a host of things where that would come into play.  It could also be because I wasn't always paying that much attention ;)



Hey, the boards were a bit slow this morning, so I figured I'd stir it up a bit...   ;)

So BFI is the only one allowed to have fun sometimes?
Not at all, it's just not always clear when people are having fun. ;)  That's one of the problems of the forum, and why I try to use emoticons so people know I'm not taking things too seriously ;D ;D ;D.

You're good with 1 cup DME to 4 cups water?
Nope, like I said (http://www.homebrewersassociation.org/forum/index.php?topic=5933.msg71090#msg71090), 1/2 cup DME to 4 cups of water is a better ratio for a starter IMO.
Title: Re: My first yeast starter - questions!
Post by: jivetyrant on February 15, 2011, 01:04:26 PM
Ok, so I tossed the original starter and picked up 3 slap packs of Wyeast 1056 American Ale. (propagator packs, not activator packs)  Mr Malty calls for a 3.26 liter starter using 2 of the 3 slap packs (I bought an extra to keep as insurance) and 326g DME, roughly 11.5oz if I did my math correctly.  It recommends 1g DME per 10 ml final volume.  The next problem is that my flask only hold 2000ml, yikes!  Any recommendations for alternative vessels to prep my starter in, or should a 2000ml starter be sufficient?
Title: Re: My first yeast starter - questions!
Post by: Hokerer on February 15, 2011, 02:40:34 PM
It's not a good idea to try and get the full 2L of starter in a 2L flask.  Since it gets skinnier as it nears the top, you're reducing the surface area through which oxygen gets exchanged and the whole point of a starter is to get plenty of oxygen to the yeast for growth.

For a bigger vessel, lots of folks use a 1 gallon glass juice/cider jug.
Title: Re: My first yeast starter - questions!
Post by: tygo on February 15, 2011, 03:16:57 PM
Also, if you fill it up that much, even with foam control you're likely to have it blow out of the container.

I used to use a plastic gallon jug for two liter starters.  Best to use one that contained water rather than milk for sanitation purposes.
Title: Re: My first yeast starter - questions!
Post by: a10t2 on February 15, 2011, 04:00:29 PM
3 slap packs of Wyeast 1056 American Ale. (propagator packs, not activator packs)

If you have three Propagators, there's no way you're going to get to your target cell count in a single step. Three Propagators will be ~75 billion cells, and for a 1.104 ale the target would normally be ~350 billion. According to the "intermittent shaking" option on the MrMalty calculator, you'd need an 6.4 L single-stage starter. Or you could do a 1 L first stage and 2 L second stage.
Title: Re: My first yeast starter - questions!
Post by: jivetyrant on February 16, 2011, 12:49:16 PM
Am I using MrMalty wrong?  I put in my OG or 1.104, type as ale, volume as 5.00 gallons, production date as 2/2/2011 for an 87% viability rate. Liquid yeast, intermittent shaking, default growth factor.  It gives me 348 billion yeast cells needed, 4 slap packs needed without a starter, 2 slap packs needed with a starter, starter volume of 1.91 liters.

Also, I bought a quality $11 gallon glass jug of some really top shelf wine, which was promptly donated to the kitchen sink.  I would imagine that would be sufficient for most of my starter needs!
Title: Re: My first yeast starter - questions!
Post by: Mark G on February 16, 2011, 03:12:41 PM
The Propagator packs contain only 25 billion cells, while the Activator packs have 100 billion cells. The Mr. Malty calculator works under the assumption that you're starting with Activator packs. And good purchase on the gallon jug. Those are perfect.
Title: Re: My first yeast starter - questions!
Post by: jivetyrant on February 18, 2011, 02:55:25 AM
Prepped a 1L starter with 3.5oz of DME and pitched all 3 Propagator packs.  It's definitely a lot more active than my last one was!  When I shake it it foams right out the top of it's 2000ml flask!  I'll pitch to a 2L secondary starter when this one slows down, from what has been said that should get me pretty close to the cell count I'm looking for.  If not I have several packets of dry S04 and S05 I can fall back on, I can't imagine I'd have problems mixing the yeast strains.

When its done I plan to decant off nearly all the liquid and then shake it a bit to get the yeast cake back into suspension then pitch that straight to the carboy.  Is that correct?
Title: Re: My first yeast starter - questions!
Post by: Hokerer on February 18, 2011, 03:06:13 AM
When its done I plan to decant off nearly all the liquid and then shake it a bit to get the yeast cake back into suspension then pitch that straight to the carboy.  Is that correct?

That is correct
Title: Re: My first yeast starter - questions!
Post by: jivetyrant on February 19, 2011, 12:18:03 PM
I ended up running out of time and wasn't able to do the second yeast starter I had planned on.  I am now left with a standard 1L starter with 3 propagator packs in it.  I am planning on pitching that and supplementing with some rehydrated dry yeast.  I have several varieties available to me. (I keep a stock of dry yeast in case of mistakes or emergencies such as this)

I have US-05, US-04, S-33, T-58, Nottingham and Windsor.  Any reccomendations. (It's an Imperial Stout, 1.104-1.110 OG)

Edit: I am leaning strongly towards the US-05 as it seems the most similar to the Wyeast 1056 American Ale I'm using currently.
Title: Re: My first yeast starter - questions!
Post by: a10t2 on February 19, 2011, 02:37:22 PM
Yes, US-05 and 1056 are essentially the same yeast.
Title: Re: My first yeast starter - questions!
Post by: punatic on February 28, 2011, 12:19:48 AM
I don't know...how about:
As porosity goes to 0, bulk density approaches particle density.
;D  That works.  I don't remember that phrase from any of my classes, but that could be because they were mechanical engineering or biochemistry classes, not civil engineering or materials science or soil or any of a host of things where that would come into play.  It could also be because I wasn't always paying that much attention ;)

Geotechnical engineering, Environmental engineering, Hydrogeology...
Title: Re: My first yeast starter - questions!
Post by: ronrock on March 07, 2011, 01:32:19 PM
jivetyrant, How did the fermentation go?
Title: Re: My first yeast starter - questions!
Post by: jivetyrant on March 07, 2011, 01:52:59 PM
     Well!  I tossed the first starter that I made, it was showing very little activity.  As suspected by a few folks the starter's OG was far too high.  I ended up following the instructions on MrMalty for my second starter.  I did a 1L starter using 3.5oz DME and a bit of yeast nutrient. (1g DME per 10ml final volume)  This starter showed great activity!  I did not have time to increase to a larger starter so I instead supplemented the starter with an 11.5g pack of rehydrated S-05.  Fermentation proceeded quite quickly and topped out at a somewhat disappointing 1.042, roughly a 63% attenuation. (I started a separate thread regarding the stuck fermentation.)  I added some more yeast nutrient, pitched some more rehydrated S-05 and a touch of sugar to get it working, shook the carboy *very* thoroughly in the morning and at night, making sure there was no yeast sediment on the bottom before stopping.  I raised the temp a bit, bumping it closer to 75-80.  2 days later I went to check my gravity and....... promptly dropped my hydrometer and smashed it to bits. -.-

     My new hydrometer arrived in the mail yesterday.  I swung for a (hopefully) more swish model, choosing a thermohydrometer from northernbrewer.  Will probably check the gravity tonight or tomorrow! 
Title: Re: My first yeast starter - questions!
Post by: ajk on March 07, 2011, 02:05:10 PM
  Storing it in the fridge will cause a longer lag time when you pitch it into the wort. 

Could you expand on this? Myself and lots of excellent homebrewers have followed numerous commercial breweries lead of pitching cold.

I don't know about lag time, but I alway try to keep starters around the same temperature as the wort because of the following from Jamil's site (http://www.mrmalty.com/pitching.php):

Quote
According to Dr. Clayton Cone, one of the foremost experts on yeast, the yeast should be within 15F of the wort they're being pitched into. Neva Parker, the Laboratory Manger at White Labs, suggests a maximum swing of 10F and ideally 5F. I agree with Neva 100%. Besides shocking and stressing the yeast, pitching warm yeast into a cool wort can cause many of the yeast to produce petite mutants, which will never grow or ferment properly and they can produce excessive H2S.
Title: Re: My first yeast starter - questions!
Post by: denny on March 07, 2011, 04:32:41 PM
  Storing it in the fridge will cause a longer lag time when you pitch it into the wort. 

Could you expand on this? Myself and lots of excellent homebrewers have followed numerous commercial breweries lead of pitching cold.

I don't know about lag time, but I alway try to keep starters around the same temperature as the wort because of the following from Jamil's site (http://www.mrmalty.com/pitching.php):

Quote
According to Dr. Clayton Cone, one of the foremost experts on yeast, the yeast should be within 15F of the wort they're being pitched into. Neva Parker, the Laboratory Manger at White Labs, suggests a maximum swing of 10F and ideally 5F. I agree with Neva 100%. Besides shocking and stressing the yeast, pitching warm yeast into a cool wort can cause many of the yeast to produce petite mutants, which will never grow or ferment properly and they can produce excessive H2S.

Notice that says pitching warm yeast into cool wort.  I've had excellent results pitching cold yeast into warmer wort.  It comes out of the fridge and right into the beer.
Title: Re: My first yeast starter - questions!
Post by: Mark G on March 07, 2011, 04:37:33 PM
This came up a while back on the forum, and since then, I've been keeping my starters in the fridge until I'm ready to pitch. Then decant, and pitch cold. It's been probably 10-15 batches, and I haven't noticed any difference in yeast performance.