Tosna and clearing of racked mead

[apisgallus]

This might be a long post, forgive me, but I'm clearly missing something (no pun intended to my original post.
Following Travis' Advanced Nutrients in Meadmaking very thorough PDF.
Here's what I calculate, starting at SG1.11 (2.75 lbs of my honey), the YAN needed is approx 220 ppm for medium yeast ec118 or kv116 (p7)
Must contributes about 30 (p4), meadmaker recommends 2.5 of Go-ferm and 1.1 g of FermO. on page 10 of ANM the table states that GoFerm at 1 g/L adds 30 ppm YAN, so 2.5 g in 3.6L (1 gallon ish) will provide 20 ppm, similarly for Fermaid O , 1g/L adds 40 ppm yan so 4 g adds almost 50 YAN. adding these together 30 +30+ 50 gives me 110 ppm, almost half the 220 ppm required. What am I missing. I've worked in a lab so I should have not messed up calculations

 

[balathustrius]

The GotMead calculator estimates SG 1.099 for 2.75 pounds of honey in 1 gallon of mead. But I'll use 1.110 so that we're working from the same data.

1116 and 1118 are both listed as low-requirements by Lalvin.

30 PPM is sort of the maximum you can expect for a traditional must - even that would be an outlier. You're more likely dealing with 10-15 PPM - and TBH I usually just set it to zero and ignore it.

Regarding nitrogen from GFPE, if you read a bit farther down, page 13 I think:

A quick rule of thumb is that if you’re using 2 g of yeast per gallon of must - the standard pitch rate - and rehydrating in the correct amount of GoFerm (grams of yeast * 1.25), you’re adding approximately 20 PPM nitrogen. If you use a whole 5 gram packet of yeast and 6.25 grams of Go Ferm on a single gallon of must, however, you’re adding over 50 PPM. Keep in mind that some dry yeast packets are 11.5 grams, or some other weight entirely.

I also typically ignore this, but I also pitch at that rate - not a whole 5g packet for a 1 gallon must.

---

Okay here I'll outline my approach for a 1.110 starting SG mead.



I would rehydrate 5 g of yeast (a packet) in 85 ml of water with 6.25g of GFPE*. After rehydration I would measure out about 35-40 ml of the yeast slurry and pitch with that, and either use the rest on another batch or discard it. If you make two 1 gallon batches it works out to a slightly heavy pitch, definitely not a big deal.

*I don't try to work with less than that because IME the water cools down very quickly and they don't get a nice lingering rehydration bath.

Then I would follow the calculator as above, split into several additions however makes sense to you - but I do Fermaid O up front (all of it 24 hours after pitch), then the F-K+DAP mixed together and distributed over 3 or so additions.

In total, I am adding about 20 PPM (GFPE), 215 PPM (addition schedule), and there's <20 PPM present to start with. You could put 20 in the Offset PPM field if you wanted, but slightly overdoing it is probably better that slightly under.

Does this help?

Note: I am the author of ANM. I don't post here a lot, so I apologize if I'm slow about answering questions.

 

[Medsen Fey]

. adding these together 30 +30+ 50 gives me 110 ppm, almost half the 220 ppm required. What am I missing. I've worked in a lab so I should have not messed up calculations

Those numbers look reasonable though the 30 ppm from the honey may be generous. The Go-Ferm does give nitrogen comparable to Fermaid O which helps bring the nitrogen up. I apologize if I misunderstood the amounts you are adding. Having 110 ppm YAN from organic sources should probably work, though I usually go with higher amounts.

I find staggering the nutrients to be unecessary when using totally organic nitrogen. Staggering nutrients was important when using DAP as a main nitrogen source because the yeast would over-eat as they absorb ammonium nitrogen more easily and preferentially to organic nitrogen. I think the staggering with organic nitrogen sources is habit that lingers from the old days.

 

[apisgallus]

please forgive me missing the point, but the numbers for fermaid O only still don't add up in my brain.

If you need approx 220 ppm and according to all calculators, must, GoGerm and fermaid O only contribute about half the 220 ppm.
What am I missing?

Given that my last batch fermented within a week to 10 days to 1.000 14.4% with KV16 and EC1118. It went according to plan, first rack taste seemed on par with other batches, but does not seem to clear.
Is it the general observation with TOSNA that a/meads will take a longer time to clear (overall), or B/ some finings treatment is necessary.

I really appreciate all your help on this

 

[balathustrius]

I'm not following your math, but are you multiplying the actual PPM YAN from Fermaid O by 4? The number we use for Fermaid O isn't the actual PPM YAN that it adds, but an effective number. It is 3-4x more effective than the actual number. So if you're adding 20 PPM YAN from Fermaid O, you should think of it as more like 60-80 PPM YAN for the purpose of calculating how much you are supplementing the must.

See the following section (from ANM):

 

[apisgallus]

I'm not following your math, but are you multiplying the actual PPM YAN from Fermaid O by 4? The number we use for Fermaid O isn't the actual PPM YAN that it adds, but an effective number. It is 3-4x more effective than the actual number. So if you're adding 20 PPM YAN from Fermaid O, you should think of it as more like 60-80 PPM YAN for the purpose of calculating how much you are supplementing the must.

See the bolded section (from ANM):

View attachment 1921

Thanks for explaining this. Now it makes a lot more sense. BTW I teach wastewater and drinking water operators and there is a lot of basic matth involved. I have to understand the math every which way to teach it, which is how I approached this calculation. the 4 x factor I somehow missed. Really appreciate your patience.

 

[Maylar]

used 1/4 cup tea and citrus peel

Did your other batches have citrus peel too? That is a major source of pectin.

 

[apisgallus]

just take the outer zest of 1/2 orange

 

[balathustrius]

Thanks for explaining this. Now it makes a lot more sense. BTW I teach wastewater and drinking water operators and there is a lot of basic matth involved. I have to understand the math every which way to teach it, which is how I approached this calculation. the 4 x factor I somehow missed. Really appreciate your patience.

Yeah, looking through ANM to find the right section, I realized that it's only mentioned in the notes for FO, and I've made a mental note to expand on that somewhere next time I do a significant edit.

 

[apisgallus]

Yeah, looking through ANM to find the right section, I realized that it's only mentioned in the notes for FO, and I've made a mental note to expand on that somewhere next time I do a significant edit.

Thanks,
I thought I was losing my ability to do math.