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THawk
06-20-2012, 03:49 AM
I'm not sure if I have this right... Please correct me if I'm wrong...

OG (based on calculator): 1.108 (6 lb honey, 2 gallons)

So I would be aiming for a theoretical FG of 1.0 so I would base my feeding on how far along the fermentation is towards 1.0 (or towards what I'm aiming for)?

Assuming what I'm aiming for is 1.000, then the 1/3 break is 108/3 or 1.072. So I'd add 1 teaspoon of nutrient (measurement per the Newbee guide) to the ferment?

Is this correct or am I out in left field here? :confused:

Yo momma
06-20-2012, 06:32 AM
Well I can say this is a very common question. There is tons of info on this site about it.

What I do is take my OG - FG= answer. Divide answer by 3. Subtract answer from the OG and then again from that answer giving me my staggered feeding.


1.130 OG - 1.015 FG = .115 / 3 = 38

Roughly around 1.100 first feeding and 1.065 final feeding. Remember that at 1.060 your yeast will not absorb the food you give them. Hope that helps.

THawk
06-20-2012, 09:35 AM
So the 1/3 break is around 1.092 (or about 1.100) you'd add nutrient into the must and mix it (or can I dissolve it in part of the must, shake it up, and pour the lot back in)?

Where do you get 1.065 for the final feeding (or is that just 1.100 - .38 )?

Also where do you get 1.060 (or is this some documented point?

Sorry -- I'm used to pitching the nutrient in at the beginning and letting it run for 2 weeks or so...

Does step feeding make the yeast more efficient?

Chevette Girl
06-20-2012, 10:49 AM
First, a comment... step feeding is usually when you're adding more honey near the end of a ferment so as to get a high alcohol end product without giving your yeasties a rough start with a really high gravity... staggered nutrient addition is usually how we refer to what you're talking about - separating your nutrient additions into more than one big addition.

Usually you want to add some of your nutrients as soon as lag phase is over (visible signs of fermentation) so the new yeast have something to work with but don't go too crazy and poop out early, then as their population gets larger, you want to feed them a little more a little later, usually by the time they've eaten a third of the available sugar.

For your 1.108 gravity, subtract your FG (in this case 1.000), divide the resulting .108 by 3, (I get .036) then subtract this number from your OG (1.108-.036 = 1.072) to get your 1/3 sugar break.

My lazy staggered technique is I add half of the total amount of nutrients I'm planning to add to the batch after lag (currently I'm going with 1/2 tsp nutrients, 1/2 tsp energizer, subject to change based on yeast and fruit used), and then I mix the rest in a container and give it a sprinkle after every aeration and I try to time the amounts so that the last bit goes in around the 1/3 sugar break when I usually stop aerating.

That said, I front-loaded for years and I honestly don't know how much difference it has made. I shall have to try an experiment some time so I can see for myself if it's worth the bother :)

THawk
06-20-2012, 12:27 PM
so past the 1/3 break, no more nutrients should be added?

wayneb
06-20-2012, 03:16 PM
Well, no. That's not entirely correct. I'd suggest that for a more thorough explanation you search on the terms 'staggered nutrient addition' for postings made by the mead mentors here (including myself, Medsen Fey, Akueck, etc.) and you will find pages of information about how it works.

But the short answer is that post-1/3 sugar break your yeast are less able to utilize nitrogen from inorganic sources (such as DAP) than from organic compounds. And by the time your must reaches the 2/3 break, virtually no inorganic (sometimes called non-amino) nitrogen will be taken up by the yeast - and even though they can still process amino nitrogen sources, nutrients provided that late in the game are not as effective as if they had been made available earlier in the fermentation. BUT, providing too much yeast assimilable nitrogen (YAN) too early in fermentation can set off an explosive growth in yeast cell numbers, followed by a long-term stress; yeast don't like to be overcrowded any more than people do, and if they are, they can be really stinky about it. So it is better to give them something that they can use, when they can use it. That's the foundation for staggered nutrient additions.

Yo momma
06-20-2012, 07:11 PM
Wayne is the guy I learned how to stagger my nutrien, so he has ( swagger) stagger, lol, so listen carefully and you will easily get it down to an art.

akueck
06-20-2012, 07:22 PM
I like to think of it with a running analogy. Your yeast are in for a marathon, not a sprint. If you jack them up on nutrients, they'll gorge themselves on the sugar, run like hell, and then crash before they get to the finish line. That's really bad pacing. You want your yeast to run at a good clip, but not tire themselves out by sprinting in the beginning. So the staggered nutrients get you the steady pacing.

THawk
06-26-2012, 02:09 AM
I currently have access to Fermax Nutrient (similar to Fermaid K) and Yeast Energizer. Should I purchase DAP as well (even though both the Fermax and the Energizer have it)? Also how does one use Go-Ferm?

Chevette Girl
06-27-2012, 02:03 PM
Go-ferm is a rehydration aid.

I think having DAP on hand as well as energizer is a sound plan, as I suspect yeast needs more nitrogen than the other stuff (micronutrients, etc) found in the energizers, and (for me anyway) DAP is about a third of the price of energizer.

THawk
06-28-2012, 09:23 AM
I think having DAP on hand as well as energizer is a sound plan, as I suspect yeast needs more nitrogen than the other stuff (micronutrients, etc) found in the energizers, and (for me anyway) DAP is about a third of the price of energizer.

So when I add nutrients, can I just mix them in a separate container (e.g. honey bottle with some water and shaken to heck) or should I add it directly to the fermenting must and give it a swirl (slowly to prevent MEAs)?


Usually you want to add some of your nutrients as soon as lag phase is over (visible signs of fermentation)...

Is that the point when the airlock starts burping?

So it's pretty much - rehydrate with some nutrient, then gradually add the total nutrient until the 1/3 sugar break?

akueck
06-28-2012, 06:07 PM
I usually mix the nutrients into a tiny bit of water. Just enough to turn it into a slurry, you don't need to use a lot of liquid.

I consider the lag phase to be over when you can tell it's fermenting. Usually this is some surface bubbles, etc. Airlock movement can be deceiving.

Chevette Girl
06-29-2012, 11:46 AM
So it's pretty much - rehydrate with some nutrient, then gradually add the total nutrient until the 1/3 sugar break?

Rehydrate with water or go-ferm only (unless the manufacturer's instructions indicate otherwise), if you add anything with DAP to your rehydration water, you're asking for trouble.

I often add my energizer up front because it's got less DAP than straight nutrients, but you really want to wait until there's airlock activity (or visible bubbling, about the only time we use these signals as an indicator) that indicates the SG is starting to drop before you add any heavy DAP additions.

But yes, generally, you want to add your nutrients and energizer between end of lag and 1/3 sugar break.

THawk
06-29-2012, 06:27 PM
if you add anything with DAP to your rehydration water, you're asking for trouble.

Just curious -- what happens? :)

Chevette Girl
07-01-2012, 01:00 AM
Explosions, chaos, rioting in the streets, and a meteorite hits your house. ;D

Sorry, it's too late and I'm too lazy to go look up the references for you, although you'll probably find some if you look up making acclimated starters because a lot of folks think they'll help their yeasties by adding DAP and Fermaid to rehydration or early starters, and failing that, reading up on staggered nutrient addition.

In summary, your dehydrated yeasties need water, just water, or something like go-ferm which is formulated specifically not to harm rehydrating yeasties. If you add anything like high amounts of sugar to the water while they're rehydrating, it can negatively affect the rate of hydration (osmotic pressure) and if you add chemicals like DAP, you can end up chemically "burning" your yeast because their rehydrating cell walls can't deal with it yet.

Squatchy
12-10-2014, 08:56 PM
I have read in many places on the interweb that you should stop feeding your bugs any nitrogen past the .5 sugar break. I asked a person here that I totally respect about this as it is conflict with some of the scientific info available. His answer totally hit home with me. The manuals written by the white coat lab guys were all written with a bent towards wine making. My mentors response was that with his trials he has found better results but adding at the pitch, 1/3, 2/3 sugar breaks.