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Messages - woodlandbrew

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Yeast and Fermentation / Re: Gravity for 1 pack dry yeast?
« on: December 10, 2014, 12:33:15 PM »
Here is another experiment you may be interested in:

Yeast and Fermentation / Re: C.white or Kai's yeast growth models
« on: December 10, 2014, 12:29:23 PM »
I trust Kai's model, but I might be biased.  Back when he was developing his algorithms he asked me to see if i could duplicate some of his results.  Kai's is actually based on results of starters on stir plates where C.White's is a shake flask culture experiment that was scaled up a little to account for the additional oxygen. 

Yeast and Fermentation / Re: More starter questions
« on: August 13, 2014, 04:13:10 AM »
Thanks, I hope it will be useful to brewers at all levels.  More details here:

Yeast and Fermentation / Re: More starter questions
« on: August 12, 2014, 05:36:15 PM »
Dont sweat it, what you did is fine.  your cell count might end up higher than estimated.  I've found that the final cell count of a starter is the same for stirred or intermittently shaken starters.  The big difference I have seen is the time the take to complete.  The main driver of cell count is the amount of extract.  1g of sugar will yield about 1 billion cells.  This follows the Balling Observation.

I'm working on a cell density meter that would let you know when you have reached the cell count you need for your beer.

Yeast and Fermentation / Re: Repitching slurry
« on: August 12, 2014, 05:00:59 PM »
Cell counts I have done show that Mr. Malty assumes the worst for viability.  In the fridge viability drops very slowly.  See here for details:

Yeast and Fermentation / Re: Yeast for gallon sized fermentation
« on: February 21, 2013, 03:23:10 AM »
+1 to eyeballing a fraction of the package.  That should give you a better idea of how your test batch's might scale up to full batches.

Yeast and Fermentation / Re: Manufacturer Attenuation Figures
« on: February 18, 2013, 08:32:31 AM »
Agreed with the other posters here.  The number is apparent attenuation, but it's more if a relative measurement.  You could likely get close to that if you mash at 150°F, pitch 10 million cells per ml into a 10°P wort and ferment at 20°C, but chances are that's not the beer you are going for. 

Recently I did a matrix of 40 fermentations with wort gravities from 3°P to 15°P and inoculations rates from 30 million per ml to 120 million per ml and was quite surprised by the variation in attenuation.

Data will be on my blog soon.

Yeast and Fermentation / Re: Determining Yeast Viability
« on: February 10, 2013, 07:06:18 AM »
Brett does seem to require more stain than most of the Sacc strains.  White Labs (and the Yeast book that got their information from Chris White) suggest a 0.01% MB.  This works well for about half of the Sacc strains that I have worked with.  For Brett is seems like 0.06% or 0.1% works much better.  I haven't checked MB staining of Brett against a plate or slide culture, but the numbers that I get with the 0.06% MB seem much more reasonable.  It also seems to "light up" the cells much better.  Also a 0.1M solution of Glycine works fairly well for un-flocculating the cells.  The acetic acid MB solutions do a much better job of un-flocculating, however it also seems to strip some of the MB stain out of the cells making the count more difficult and therefor error prone.

Here is some work BKYeast did on this subject:

And here is my procedure:

Others might beg to differ, but in my experience...

Mash temperature has negligible effect on efficiency.  Ditto for mash time.  Ditto for water to grain ratio (i.e., qts/lb).  If you mash in some water at 148 to 154 F for 40+ minutes, you're going to make beer at an efficiency that is mostly affected only by the extent of the crush.  Beyond the crush, very little matters.

My experience.  YMMV... but I doubt it.
This has been my experience as well.  60 minute or 90 minute seems to provide the same conversion efficiency for the most part.  To get a more fermentable mash, low temperatures and (perhaps to a lesser degree) long times seem to help.

Crush is king when it comes to conversion efficiency.  When it comes to laugtering efficiency it seems mostly driven by the amount of water collected compared to the amount of water added to the mash.

See here for details:

Yeast and Fermentation / Re: Wyeast - refrigerate ASAP
« on: January 01, 2013, 07:22:32 AM »
The lag phase can be pretty long, especially if the yeast has come out of stressful conditions.  You aren't going to see much activity until the exponential growth phase.  Here is some observations I recorded recently when propagating some low viability yeast directly following a fermentation.  It took about 12 hours to start, but 2 days would not be uncommon.

Your plan to stay the course sounds good.  You will want to aerate well.  Pouring the wort between two buckets or a kettle until the foam is threatening to come out of the bucket will ensure that you are at the saturation point of O2.  That will yield 8-9 ppm of O2 which should be plenty unless your OG is above about 1.050

Yeast and Fermentation / Re: Wyeast - refrigerate ASAP
« on: December 30, 2012, 04:42:22 AM »
How are you checking yeast health?  From what I've read, the methylene blue stain is not accurate below 95% viability.
I've read that too.  It is "not accurate" to some level.  Even the American Society of Brewing Chemists calls it not accurate.

If by "not accurate" you mean that it is not exact then I agree.  There is some error, but that error can be determined so that the accuracy is known.

It is very dependent on the strain and how much Methythele Blue that is used.  WLP004 and WLP566 stain just fine with 0.03% MB, but EC-1118, and WLP650 are better with 0.06% and 0.1% respectively.  It's also very dependent on the operator.  MB staining is very difficult to use on some strains, and there doesn't seem to be one concentration that works for every strain.  If you use too much it will actually start to kill some of the weaker yeast cells.  The method isn't perfect, but it has it's place.

I have a blog post on this coming up. 

One of my batches recently some of the grain escaped from the bag, and I was still fishing them out when it came time to bottle.  Use a bag for sure. 

It sounds like you might have enough grain to warrant the use of a 5-gallon paint strainer bag.  You defiantly want the grains to be able to swim. 

Here's my little BIAB setup:

Ingredients / Re: Water Check - not Happy with "Pale Ale" profile
« on: December 29, 2012, 04:32:14 PM »
Another +1 for lowering the Epsom.  Maybe bring up the CaSO4 to get the SO4 level you are looking for?  Both the yeast and the mash generally like Calcium.

Here are the basics I follow:

Yeast and Fermentation / Re: Wyeast - refrigerate ASAP
« on: December 29, 2012, 04:28:11 PM »
Viability doesn't drop much in a week out of the fridge, but I've never tried a month.  It could work, but will take some time to get going.

Yeast and Fermentation / Re: Yeast Starter for a 12 Gallon Batch
« on: December 28, 2012, 06:29:03 AM »
The Plato numbers are rounded.  The numbers are simply a guess.  The 9 degree Plato Line is from Yeast Calc or Mr. Malty.  They use nearly identical equations.  I'm looking forward to seeing Kai's results as well.

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