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Messages - narcout

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1
Yeast and Fermentation / Re: Are We All Overpitching All Dry Yeasts?!
« on: September 23, 2016, 12:25:28 PM »
Basically, you are pitching a certain number of cells into your wort (X) which then grows to a larger number of cells (Y) during the growth phase.

If you calculate Y as the max cell density per liter of wort and estimate X, there is a formula you can use to determine how many growth cycles it takes for X cells to become Y cells.

It isn’t really necessary.

More info can be found here if you are interested:  https://www.experimentalbrew.com/blogs/saccharomyces/yeast-cultures-are-nuclear-weapons

2
Yeast and Fermentation / Re: Are We All Overpitching All Dry Yeasts?!
« on: September 23, 2016, 10:28:03 AM »
What I mean is that you want to pitch at your target rate (whatever that may be), not be at your target rate after several replication periods.

Assuming a max cell density of 200B cells per liter, Philbrew's analysis below was correct.

If you want the beer at high kraeusen to have 200B cells/liter* in 21L, that's 4200B cells.  If you want to get there in 4 doublings (should be enough lipids for 4 replications without O2), you need to start with 262.5B cells.


3
Yeast and Fermentation / Re: Are We All Overpitching All Dry Yeasts?!
« on: September 23, 2016, 09:41:02 AM »
I think you've accidentally squared the math.  For a standard beer of about 1.055 OG, you want 7B cells/liter, so in 21L (5 gal), that's ~150B cells/5 gal, or let's say 200B like you had.  Not 4200B!!!!  So divide 200B by 16 and you get... 12.5B, which is only a quarter of a sachet for 5 gallons!!!!

I think you are confusing the recommended initial pitch rate from the paper you linked to (1M cells per milliliter per degree Plate) with final maximum cell count (200B cells per liter).


4
Ingredients / Re: Brewtan B
« on: September 21, 2016, 11:58:39 AM »
I'd be curious to hear from the manufacturer on the storage issue.  Question for the podcast maybe?

I've been vacuum sealing it for no particular reason.


5
General Homebrew Discussion / Re: Experimental Brewing podcast Episode 23
« on: September 16, 2016, 09:34:36 AM »
The Russell Everett interview was a good one.

6
Yeast and Fermentation / Re: Best Way to Aerate Wort
« on: September 15, 2016, 10:48:21 AM »
If there's enough cells in a dry yeast pack such that there is no cell growth, you could never have an overpitch by re-using a yeast cake, right?

If you pitch a single packet of dry yeast into 5 gallons of wort, there will be several replication periods.

If you assume maximum cell density of 200 billion cells per liter, a 5 gallon batch size, and that a dry yeast packet contains 200 billion cells (I don't know how many cells a dry yeast packet actually contains), you are looking at approximately 4.2 replication periods.  If you assume there are 400 billion cells in a packet, you are looking at approximately 3.2 replication periods.

S.C. laid out the math here:  https://www.experimentalbrew.com/blogs/saccharomyces/yeast-cultures-are-nuclear-weapons

I suppose you could pitch enough yeast so that there was little or no cell growth, but I believe it would negatively impact flavor (that would be an interesting experiment).

7
Yeast and Fermentation / Re: Best Way to Aerate Wort
« on: September 14, 2016, 01:19:30 PM »
Is it correct that dry yeast needs no aeration at all?

Thanks in advance for your replies.

http://www.lallemandyeast.com/articles/crabtree-effect-and-overflow-metabolism

"When the wort has more than >0.2% sugar, the function of the O2 is to assist the yeast in producing lipids. The lipids in the cell wall act as a growth factor by keeping the cell wall fluid, allowing buds to form. The production of these lipids require trace amounts of oxygen to move the squalene to the lipid stage. With out O2 the mother cell cannot produce any lipids and must shares her lipids with her daughter cell. This can occur for about 3 - 4 cycles before the cell wall becomes leathery and will not allow a new bud to form. Active Dry Beer Yeast initially contain enough lipids in their cell wall for 3 - 4 growth cycles. This is enough to complete most beer fermentations."

8
Ingredients / Re: Brewtan B
« on: September 12, 2016, 02:43:11 PM »
Why would you expect it to have sulfur issues?

I didn't, but others have raised it as a concern when removing all copper from a system. 

I also read the GBF regularly, and some people there have had issues with sulfur, though it is mostly (or maybe only) in the context of brewing ales with the lodo techniques (no copper, SMB, etc.).

9
Ingredients / Re: Brewtan B
« on: September 12, 2016, 01:18:14 PM »
For what it's worth, I tapped a Saison yesterday which was chilled with a new stainless chiller, and it does not have any sulphur issues (no SMB in this batch though).

10
Ingredients / Re: Brewtan B
« on: September 11, 2016, 12:49:02 PM »
Does anyone have any large scale blind triangle tests planned? 

11
Ingredients / Re: Brewtan B
« on: September 10, 2016, 10:48:47 AM »
I'm still hoping to see if its purported ability to coagulate and flocc proline containing proteins results in less chill haze and time to clear.

My first brewtan batch was a dry hopped pale ale that was consumed quickly so it wasn't a good test, but I currently have a Saison carbonating and a Belgian Strong Golden fermenting.


12
General Homebrew Discussion / Re: What's Brewing this Weekend? 01/18/2014
« on: September 02, 2016, 11:30:31 AM »
I kegged a batch of saison last night, and tonight I'm planning to brew a Belgian strong golden.

14
General Homebrew Discussion / Re: 30m boil help
« on: August 29, 2016, 09:33:04 AM »
Phil, I hear you but according to Wyeast (who only sells it at this time to breweries who buy it in big quantities) Brewtan B is "extracted from renewable plant materials specifically for the brewing industry".

According to the spec sheet, it is extracted from the galls of the Chinese Sumac (Rhus semialata) or the leaves of the Sicilian Sumac (Rhus coriaria). 

15
I finally had some time to get a few things done in the brewery.  Friday night I made a starter for next weekend's Belgian Strong Golden, yesterday I bottled 3 gallons of brett cider that's been sitting on oak cubes since January, and today I'm chilling down a batch of saison that I plan to keg in a few days.

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