Question of Stagered Nutrient Additions (SNA)

[ACbrewer]

I suppose this question could apply byond Mead to other drink, but I'm making a mead.

When doing a staggered nutrient addition (sna) do you take all the nutrient recomened and then divide that out through several addtions? or do you add some other amount.

Right now I'm doing 5 gallons with Wyeast 4184 (sweet mead) . This is a traditional at this point with 12.7lb honey (bought by the lb and the 'guessed' at the stop point og was about 1.085@79F) about 4.5 g water (total was about 5.5 gal). Also nuetrient - nothing else. I need to add 1 cup of earl grey tea for some tanin, I plan to do that tonight.

My addtions so far were at start 5 tsp of nutrient-DAP (LDcarlson) and 2.5 tsp energizer (LDcarlson). As per instructions on bottles (1tsp/g Nutrient and .5tsp/g Energizer).

12 hours later I did an aeration and added 1 tsp of nutrient and .5 of energizer.

Total has me at +20% of recomendation.


So I guess what I'm asking is if I should put in 1tsp/gal, is that total and then put some in at each break down to 1/3rd OG? Or should I go with 1tsp/g at start and then addtional nutrient after that until the 1/3 OG? (note by 1/3rd OG I mean if OG =90 then 1/3rd is at 60)

Also if putting in fruit does this change how much nutrient is added?

 

[MedsenFey]

Generally, you should calculate up the total amount of nutrient/energizer you want to add to the batch, and then break it up into stages. How you break it up is highly debatable, but if you add 2/3 at the end of lag phase, and the remaining 33% at the 1/3 fermentation point, you'll usually be OK.

I have some preference about the products I use, and prefer an energizer that has more autolyzed yeast (and looks like tan powder) such as Fermaid K.

And yes, using fruits and juices provides another source of nitrogen for the yeast, so you may need less nutrient supplementation.

 

[ACbrewer]

I've seen some references to having 250-300ppm. Are there calculators for that? and is it nitrogen, yan? or nitrogen in compound. Even a formula would be handy as I can do the math.

I understand that various products have varrious qualities. I'm just using what my LHBS has.

 

[MedsenFey]

YAN (yeast assimilable nitrogen) is the measurement we look at most commonly. Wine yeast usually need more than 150 ppm (mg/L) YAN; 200-250 ppm in most cases though some nutrient hog strains need more. The amounts needed also go up as the gravity goes up.

DAP - 1 g per liter give 210 ppm YAN
Fermaid K - 1 gram per liter gives 100 ppm YAN (one of the reasons I like Fermaid K is because Lallemand provides this number so we know what we are adding).

There are other important things beyond YAN, but we rarely calculate them.