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WorkSpace
07-04-2008, 06:46 PM
I have read about staggered nutrient additions in a number of posts, but I wasn't able to find an explanation for the reason for it. Why is this considered necessary? Why not put all the nutrients in when pitching the yeast?

wayneb
07-05-2008, 01:57 AM
Too much nutrient at once is in effect, too much of a good thing. Yeast utilize the nutrients in different ways (and will require different amounts) at various times throughout their lifecycle. Too much too soon and you run the risk of overdeveloping the yeast; they will ferment fast and furiously for a short while, and then the fermentation will either slow dramatically or stick outright. In extreme cases, nutrients can even be toxic to the yeast. However, when provided with just enough of several essential nutrients (assimilable nitrogen being one of the most important, but not the only one) at different times throughout the fermentation, your yeast will meet or exceed their rated ethanol tolerance, as well as ferment more quickly and cleanly, producing fewer off-flavors in the process.

Lallemand here in North America have sponsored much research into the care and feeding of yeast fermenting wine grape musts. Several people here have taken the wine-specific guidance borne of their efforts and refined it to support the unique needs of yeast in a mead must.

seanhagerty
07-05-2008, 10:05 AM
so, whats the recommended stagger of nutrient adds?

I have yeast nutrient and yeast energizer. which one do i add when?

Oskaar
07-05-2008, 01:41 PM
There are several variations that I use based on the mead.

The basic structure is:

1. Rehydrate your yeast with a good rehydration nutrient (I use Go-FERM since I use Lallemand Active Dry Yeast)
2. At the end of the Lag Phase add 1 gram/gallon of the following mixture (70% Fermaid-K to 30% DAP)
3. At the 1/3 sugar break add 1 gram/gallon of Fermaid-K or Fermaid-2133
4. Always monitor your fermentation daily and not any reductive odors as they can indicate the need for additional nutrient
5. Aerate daily up to the 1/3 sugar break, thereafter stir slowly daily to resuspend the yeast but NOT to aerate
6. Rack at the end of the primary into an aging and clearing vessel unless you are following a gross lees protocol

That's the basic dosing and aerating process I use.

Cheers,

Oskaar

WorkSpace
07-06-2008, 03:45 AM
Thanks for that Wayne. I will try it out with my next spirit wash, which I plan to do soon. I have always added all the nutrients when pitching the yeast. It seems to work ok, although it takes a long time to finish. First I need to experiment with aerating the wash :-\. And if staggering the nutrients will make the wash ferment quicker & give me a better a yeild, it is worth trying too.



... 2. At the end of the Lag Phase add 1 gram/gallon of the following mixture (70% Fermaid-K to 30% DAP)
3. At the 1/3 sugar break add 1 gram/gallon of Fermaid-K or Fermaid-2133...

My understanding is that the "Lag Phase" is while the yeast is replicating, and that this is over by the "1/3rd sugar break". But you speak of the two separately. Can you clarify this? Also, 1 gram per gallon - how many grams would one get in a teaspoon full? :icon_scratch:

lastbornjoker
07-06-2008, 08:28 AM
good info to know about both is found here. http://www.gotmead.com/smf/index.php?topic=6855.0

Oskaar
07-06-2008, 08:36 AM
Hey Workspace,

There's a ton of information out on these forums about the 1/3 sugar break and the lag phase. Use the forum search tool to track them down.

Cheers,

Oskaar

ken_schramm
07-06-2008, 09:39 AM
Hi WorkSpace;

I've done a little looking into this, and corresponded with Clayton Cone to find out why nutrient additions beyond one big dump were important. He taught me that yeast ferment much faster while in the growth phase, and so it is preferable to keep as many of them as possible in that phase as long as you can. They need the nutrient to build cell wall mass while reproducing. If there were one thing I could change/improve about the book, it would be recommending incremental nutrient additions.

I don't get too caught up with the 1/3 sugar depletion. The entire population does not go from growth to stationary phase uniformly and without exception. Think of it graphically as less of a stair step and more of a feathered gradient. There will be some replication going on in your yeast population well past 1/3 or even 1/2 sugar depletion, and they will keep on absorbing and using oxygen right through the fermentation. The risk of oxidation is an issue when you add more O2 than the yeast population can use later in the fermentation. I recommend an approach that you could think of as "just-in-time feeding."

There are two takes on the process outlined here. (http://www.brewboard.com/index.php?showtopic=60156) Both approaches are much better than no nutrient or all in one dump. If you would like the full text of my article, drop me a line and I can email it to you. Come to think of it, I'll ask BA what they would think of it being posted here in the reference section.

Ken

HighTest
07-08-2008, 06:29 PM
In 1998 I began reading about the timing of yeast nutrients and nitrogen additions as they related to commercial wine making. Using that information, and thoughts from Dr. Clayton Cone, I formulated a staggered nutrient addition protocol that I first presented to other mead makers while serving as a Brewboard guest moderator in November 2003 in this topic (http://www.brewboard.com/index.php?showtopic=7722).

As such,you may be interested in reviewing the current version of my Staggered Nutrient Addition (http://home.comcast.net/~mzapx1/FAQ/SNAddition.pdf) FAQ, which is located on my Website (http://home.comcast.net/~mzapx1/) along with several other mead related FAQs... :icon_thumright:

wayneb
07-09-2008, 12:07 AM
Mike! You've come up for air!! Good to see you posting again! :cheers: