Need Help Staggering Nutrients

[TrueMonty]

Hi all, round two trying my hand at meadmaking and I've got a question regarding the staggered nutrient/energizer method, specifically finding the right time to throw in the final bit at 2/3 of the target gravity.

I'm following Ken Schramm's medium-sweet orange blossom mead recipe and instead of introducing all of the nutrients at once I'm following the nutrient addition schedule found here which calls for 1/4th during hydration (I mixed into the must while the yeast was hydrating), 1/4th added around 24 hours after active fermentation, another at 48 hours and the final portion, which I have yet to add, when my OG has dropped by 2/3 of my target.

I'm hoping to hit the sweeter side with a target gravity of 1.025 and if my math is correct on this:
(1.110-[(1.110-1.025)*0.33])=1.082
then 1.082 is when I should drop the final bit in.

Now, here's where I've got a question; I've got two 5 gallon batches going simultaneously (I got a deal on orange blossom, what was I to do, say no?) and the first bucket read 1.110 as the OG, which would mean 1.082 is the time to drop in the last bit of nutrients.
However, at the 48 hour mark I decided to take a reading and I got 0.998...have I missed the time to drop the rest of the nutrients in? And how could I have a 0.112 drop in two days?

For the sake of giving as much info as possible my second bucket's OG was 1.112 and read 1.100 at the 48 hour mark, which would make 1.089 the best time to add the final bit of nutrient, which hasn't happened yet.

Both buckets were done within 1.5 hours of each other using 15 grams of Lalvin D-47 yeast, and contain about 7-9 quartered Stayman-Winesap apples (an unknown wild seedling cross-pollinated with an old English hard cider variety).

The first bucket probably had a few more apples in, we quartered 16 apples and eyeballed the amount we threw into each bucket and it looked to me like the first had more, but not by much.

Again this is only my second attempt at mead and if any of you remember last year's absolute miscarriage of an attempt then you'll know I'm completely open to any and all admonishment so long as there's actual advice and not plain old mocking.

Both airlocks are bubbling away merrily and I'm nowhere near as worried for this batch as I was with last year's but either way I thought it safe to ask the good folks at homebrewtalk, it's your professional approach mixed with a legitimate passion to help newcomers that keeps me coming back to this forum. Thanks in advance guys, and keep on keepin' on.

 

[WVMJ]

Dropped by 2/3 and at 2/3 of target are 2 different things. The yeast companies seem to favor all of the nutrient additions by 1/3 decrease in sg, other meadmakers go down to the 1/2 mark but I think that may leave to much residual nitrogen in their meads that might feed spoilage organisms or eventually give an off taste over time. The yeast companies research seems to indicate that yeast can assimilate nitrogen past the 1/3 reduction mark (which would be your 2/3 of target, not 2/3 of total). WVMJ

 

[TrueMonty]

Dropped by 2/3 and at 2/3 of target are 2 different things. The yeast companies seem to favor all of the nutrient additions by 1/3 decrease in sg, other meadmakers go down to the 1/2 mark but I think that may leave to much residual nitrogen in their meads that might feed spoilage organisms or eventually give an off taste over time. The yeast companies research seems to indicate that yeast can assimilate nitrogen past the 1/3 reduction mark (which would be your 2/3 of target, not 2/3 of total). WVMJ

It would seem that both the site I mentioned and another that I was looking at have, based off Ken Schramm's book, said to add the last staggered nutrient when it's dropped by 2/3 instead of 2/3 of target, but the first user comment on the aforementioned site states that Schramm's book is incorrect in this calculation, and that it should be 1/3 instead of 2/3, just as you said.

But then doesn't the bit of math I've got in the original post still apply? By which I mean, doesn't 1.082 mark a 1/3 drop from my OG?

Sorry if it seems like I'm not catching on quickly enough; I've started to realize that anything with fractions sends me into "Stalone in First Blood/Norris in Missing In Action" style flashbacks of math teachers yelling at me in frustration that cause me to curl into the fetal position and find a happy place...I'm going to need to get over that if I'm going to get any better at this I guess.

 

[WVMJ]

Its not the target sg that is important, the yeast have no clue what your target it, its the starting gravity, 110*0.66=1.073 as the 1/3 sugar used mark. Get the Scotts Lab fermentation guide, all the facts, ratios rational etc from the people who make this stuff is there so you can figure it out vs trying to guess which person on the net has it right. One problem is that some people keep add past that mark and it works so they think they have helped even though there is a cutoff of when yeast can use the nitrogen, still up for debate. If you leave extra nitrogen setting around something can come along and eat it, like bacteria or some yeast you dont want in there and make things funky, and excessive nutrients can add some off tastes like metallic. And, I might add, in the "old" days we just dumped everything in the first day and it all worked out just fine