# YAN Calculations



## David Violante (Dec 28, 2020)

The topic of figuring out YAN and what additions we may want or need to make as home winemakers has become a recent curiosity of mine, and I had inadvertently hijacked a Christmas Wine thread as the conversation moved from the recipe to yeast type to nutrient addition and figuring out YAN. Apologies to the OP... hence I wanted to start this thread to get feedback, wisdom, experience, and practicality from my esteemed colleagues... 

I don't have the equipment necessary to test YAN, and there are a lot of variables that go into YAN. There's really no chart that can be made to say that a particular grape (or other fruit) has a particular YAN. Fruit changes from year to year as does soil additions, water levels, when it's picked, you name it. There are some really good articles and information by extension centers and yeast manufacturers online - all very helpful in understanding YAN and what yeast requirements are as related to a must's YAN. The next question for me was, so how can we figure this out without breaking the bank, even if just a little. @dmw_chef posted a paper related to YAN in meadmaking, that references a Scott Labs 2016 handbook with a formula for calculating YAN requirements based on sugar content. The paper is here: _Advanced Nutrients in Meadmaking_ and does reference Wine Making Talk folks. There is a segment in the paper on how to make additions, and what Nitrogen content is in what products. Ex: Using GoFerm, Fermaid-O & K, DAP, and when. 

The process goes something like this:
1. Determine initial Brix using a refractometer​2. Determine Specific Gravity using a hydrometer​3. Determine the Sugar in Grams/Liter (Sugar g/L = Brix * Specific Gravity * 10)​4. Calculate Nitrogen Requirements (additions) in parts per million (ppm) based on the yeast you're using​For Extra Low N requiring strains: Sugar (g/L) x 0.5​For Low N requiring strains: Sugar (g/L) x 0.75​For Medium N requiring strains: Sugar (g/L) x 0.90​For High N requiring strains: Sugar (g/L) x 1.25​​_Scott Labs 2020 Winemaking Handbook_ has a great deal of YAN information starting on page 41 and some corresponding charts based on initial brix and yeast type YAN requirements. 

I'm curious about the position of this group and the experiences you all have in this regard. There's a ton more information out there and a lot of reasons to explore under/over using nutrients. 

Thanks in advance... David
​


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## sjjan (Dec 28, 2020)

I just got both a Vinmetrica YAN test kit as well as a CDR Winelab Junior with the ability to test for YAN. I am as well interested in this subject to see how I could improve the AF next time around without running into stressed out fermentations due to lack of nutrients.

One clue could be the pre-clearing that is done over here a lot with Bentonite just before the AF is started. They say that this might rob the juice of too much nutrients at the start of the AF already.

Interesting topic. Following along.


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## RPh_guy (Dec 28, 2020)

Edit: nevermind.


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## David Violante (Dec 28, 2020)

So after some searching around online, I came right back to _this thread_, right here, by Deezil in 2013. For some reason it didn't show up in the search on YAN. It's a great read and thoroughly explains YAN.


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## sjjan (Dec 29, 2020)

David Violante said:


> So after some searching around online, I came right back to _this thread_, right here, by Deezil in 2013. For some reason it didn't show up in the search on YAN. It's a great read and thoroughly explains YAN.


Thanks for referring to the other thread on the topic. Very interesting read!


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## Rice_Guy (Dec 29, 2020)

in part the question should be what style does one make?


sjjan said:


> I’m curious about the position of this group


* the old impression on nitrogen was do a guess on how dirty the must is (sugar free dry extract). If the fruit had a lot of solids it would ferment without any intervention. If it was a desert like dandelion wine everything is synthetic and in that case use DAP.
* before pandemic the vinters club had a talk on feeding yeast which presented the analogy that using DAP is like,, feeding candy to kids after Halloween, ... yeast love DAP but it isn’t really good for them and likely to cause problems. Organic nitrogen will always give a smoother fermentation! therefore only use Fermaid O.
* I read “The New Cidermakers Handbook”: Jolicoeur, 2013, last year which changed my assumptions on YAN. My assumptions currently follow his.
.. nitrogen management is one of the tools we have to create a naturally sweet wine without the use of potassium sorbate, by racking we can strip nitrogen when we are at 1.020 to intentionally cause a stuck fermentation at about 1.005
.. the available nitrogen depends on the ‘sugar free dry extract’ AKA ‘dirt’ in the must/ fruit, _For the most part high extract corresponds with high flavor/ lower moisture and higher YAN and is a separate trait from SpG/ sugar. _Old plants do better producing high extract, a dry year does better at producing high extract, not using nitrogen on the garden/vineyard promotes high extract, being in a dry year/climate promotes high extract. ,,, and high extract will be more likely to produce a contest winning wine.
.. every variety and every crop year will have a slightly different chemical make up, therefore the only way to really know nitrogen is to measure YAN.
.. we create a high demand for YAN by running higher temperatures in the primary, every strain of yeast will need less YAN at 10C than at 30C. 
.. and as noted from the club organic nitrogen (dirt) is better for a fermentation than chemical nitrogen.


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## dmw_chef (Dec 29, 2020)

Rice_Guy said:


> Organic nitrogen will always give a smoother fermentation! therefore only use Fermaid O.



Disagree. Inorganic nitrogen has its place and uses.



Rice_Guy said:


> nitrogen management is one of the tools we have to create a naturally sweet wine without the use of potassium sorbate, by racking we can strip nitrogen when we are at 1.020 to intentionally cause a stuck fermentation at about 1.005



Strongly disagree. Racking early does not strip nitrogen, it just strips a lot of the yeast biomass. Relying on a stall that's not delle limited or beyond the ABV tolerance of the yeast without stabilizing will always put you at risk of bottle bombs.



Rice_Guy said:


> the available nitrogen depends on the ‘sugar free dry extract’ AKA ‘dirt’ in the must/ fruit,



Kinda/sorta. To my understanding overly clarified musts lack sterols and micronutrients that yeast need during the growth phase, which is the bigger issue.


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## David Violante (Dec 29, 2020)

So how I understand YAN (at the moment but subject to change) is how it's written in the Scott Labs book and what Deezil write in 2013. This is just the background. 

_"In order to conduct a healthy and complete fermentation, yeast require minerals, vitamins, fatty acids, sterols and nitrogen. Minerals, vitamins, fatty acids and sterols are provided by GoFerm Protect Evolution™, whereas nitrogen is supplied by Fermaid O™ or Fermaid K™. If we consider the individual needs of the yeast, how much fermentable sugar is present and how much nitrogen is required by the yeast under these conditions we can tailor a program designed for success."_​-Scott Labs​​As I looked through the charts from Scott Labs and elsewhere, even in the determinations by the previous posting calculations above, I could see what the nutrient requirements are for yeasts based on sugar content (brix and/or SG). We have the ways then to meet those requirements using a variety of products like GoFerm, Fermaids, DAP, etc... and on a schedule optimized for yeast usage throughout their lifecycle and environmental change from sugar to alcohol under depleting resources. 

What I'm missing, and maybe this is indeterminable for a home winemaker, is how to know what resources exist in a must prior to nutrient addition so as not to over- or under- supply nutrients for yeast. 

Here's an example: honey is nutrient resource deficient even if used in enough volume to get a high initial brix. So, you need to add more nutrients and YAN so that the yeast are happy. Grapes, not so much but you still need to add some. Other fruit? There are a lot of factors that can change nutrient composition and YAN even from harvest to harvest (and before adding sugar and referencing a chart or doing a calculation based on yeast strain). 

If I take a gallon of must from 10 pounds of crushed grapes, and that has an initial brix of 21, it will have a different YAN than a gallon of must from 1 pound of crushed grapes with enough sugar added to equal a brix of 21. But we're basing a chart off of sugar, and what yeast need to ferment it, not necessarily what resources are already there. 

Am I overthinking it or is this just a factor of being a home winemaker and using experience and the help of others as your guide?


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## Ajmassa (Dec 29, 2020)

Great Thread topic @David Violante 
I think the nutrient analogy of:
‘fermK (or similar) = full balanced meal‘
vs
‘DAP = red bull‘ 
gives DAP a bad rep and deters some home winemakers from utilizing it, viewing as unhealthy. From what i’ve learned from other more experienced winemakers i agree with what was said above, that DAP definitely has its place and uses. 

As far as analyzing different techniques to determine what YAN c_ould_ _be_ (based on multiple variables) there’s probably a ton of useful methods in there, but 9x out of 10 a standard nutrient protocol gets the job done. Plus those methods would still just be assumptions. Why go thru all that when ya can easily know for sure?

When investing serious $ into our grapes we want to ensure a healthy ferment and eliminate any possibilities of negative issues. Only way to know for sure is testing for it. It’s actually pretty cheap. Only $32. And you do NOT need a vinmetrica to utilize it—just a ph meter with 2 decimal places. vinmetrica yan kit. i will no doubt have this before my next ferment. —I said this same thing over the summer and regret not following through. 

This past fall was the nail in the coffin. Had myself an extremely sluggish ferment, ended up abandoning my standard nutrient protocol and started step feeding nutrients daily to make sure there was enough in there to finish since it was taking so long. It did finish dry eventually and was definitely a learning experience. The rosé i also made from these Wash St. grapes however did not finish dry. (I can only assume the rosé lacked even more nitrogen & other nutrients from an already low nitrogen must via minimal maceration time)

I learned later that Washington State had an abnormally high amount of sluggish/stuck ferments this year. Had i known the YAN level i would have avoided a lot of stress potentially. Not letting this happen again.


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## Rice_Guy (Dec 29, 2020)

the issue of nutrition is extremely complex and I would question with today’s technology if there are hard and fast answers, as noted the yeast suppliers are working on defining nutritional requirements,,,, if it was easy it would be done.


David Violante said:


> What I'm missing, and maybe this is indeterminable for a home winemaker, is how to know what resources exist in a must prior to nutrient addition so as not to over- or under- supply nutrients for yeast. . . . Am I overthinking it or is this just a factor of being a home winemaker and using experience and the help of others as your guide?


ex:
* in the early days of nutrition studies with purified diets they didn’t catch that zinc is an essential nutrient since there was enough in touching the galvanized cages to supply the RMD
* in the tissue culture lab at school we used extracts (coconut milk) for the media since it was easier to get a dose of unknown required enzymes/ nutrients/ hormones than creating a purified chemical soup.
* @dmw_chef above pointed out needed sterols/ other micronutrients
* we look at crop variability based on where it was grown and the specific year, as my dad stopped adding sulfur to the fields since the coal fired power plant was releasing enough that was captured in rain for crop need or the baby food folks have started to test regions of supply since some areas are showing increased arsenic in the rice crop.
* stress/ versus excess on an organism changes growth rates as immigrants to the US frequently are taller than their foreign raised parents and the richer parts of the world are suffering an obesity epidemic
* Jolicoeur in Cider Maker is suggesting a little disease in an orchard helps create higher sugar free extract which in turn does a higher quality finished fermentation.

As a home wine maker you probably will never have enough analytical tools to know the whole picture. University folks have more tools but then it gets to what is practical and as has been done with human nutritional guidelines rules were built to be safe for 95 or 98% of the population, ,,, are known to be over kill for maybe half of the population, ,,, and are believed to not cause damage if given in excess. The folks who run plug flow fermentors are most likely to discover micronutrients since they run long enough to see the unusual/ unexpected cause vs effects.
The good news is that YAN is a gross nutrient which is easy to demonstrate a deficiency in _under defined conditions_, however change conditions as dropping fermentation temperature and more nutrients are recycled so less is required to meet peak demand.


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## dmw_chef (Dec 29, 2020)

David Violante said:


> Am I overthinking it or is this just a factor of being a home winemaker and using experience and the help of others as your guide?



IMHO, I think you are overthinking just a bit. Absent a way to measure YAN it's going to be experience and help of others. 



David Violante said:


> But we're basing a chart off of sugar, and what yeast need to ferment it, not necessarily what resources are already there.



Remember that the charts are the *total* YAN you should have for a healthy ferment; it doesn't depend on how much YAN your fermentables provide, you've got to supplement the delta. I don't do a lot of work with fruit, but I'm told by a very experienced meadmaker to does work with lots of fruit is that a reasonable baseline is to assume that each lb of fruit/gal brings 25-30ppm YAN to the table. It's obviously going to differ as you say on the fruit and lots of other factors. 

Personally, I think with good process the dangers of too much YAN leading to microbial instability are a little overstated. Nichola Hall from Scott seems to suggest that excess YAN will simply result in a larger colony and faster/hotter ferment:



I've sent a question in to check the validity of my interpretation.



Ajmassa said:


> Only $32. And you do NOT need a vinmetrica to utilize it—just a ph meter with 2 decimal places. vinmetrica yan kit. i will no doubt have this before my next ferment. —I said this same thing over the summer and regret not following through.



Interesting, I always assumed the vinmetrica yan kit needed a vinmetrica.


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## dmw_chef (Dec 29, 2020)

dmw_chef said:


> Personally, I think with good process the dangers of too much YAN leading to microbial instability are a little overstated. Nichola Hall from Scott seems to suggest that excess YAN will simply result in a larger colony and faster/hotter ferment:
> 
> 
> I've sent a question in to check the validity of my interpretation.



Reply:



> You are almost correct, just one little part that will differ.
> 
> YAN- yeast assimilable nitrogen- is a driver of fermentation rate and cell number. The work done by Prof Sablayrolles at INRA showed that the YAN you have (at the onset of fermentation) is all used up (at least the ammonia portion) by the end of the exponential growth phase (this is approx. 1/3 fermentation). The difference between two similar starting sugars, and different YANs (low v. high) is that the high YAN (if high YAN requiring yeast is used) ferment will start faster, be warmer and have many more cells. This is why we say that irrespective of what your starting YAN is, you always want to do an add at 1/3 sugar drop for a positive rate of fermentation. Of course, the yeast will continue to take up nitrogen past this point, just inefficiently, and at the tail end of fermentation the yeast actually secretes amino acids (which is one of the reasons why some yeast are friendlier to ML than others). You will always have YAN at the end of a ferment, which is why the term nutrient desert is a misleading.


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## David Violante (Dec 29, 2020)

Thank you gents, this is a lot of good information. I do tend to overthink a little, perhaps because I also want to truly understand. You know... dive in and swim under water a little before coming up for air. At some point you get to actually swimming when you combine the understanding and the experience. 

@Ajmassa I think your experience is a great example. @dmw_chef here is the manual from Vinimetrica, it indicates you need either their unit or a pH meter that goes out to 2 decimal places.

I'm still working out the math, to actually understand the right additions at the right times (ppm vs g/gall etc...) Ex: 1G/Gallon of Fermaid O is actually 10.57ppm YAN. If I need 200ppm, is the math 200 / 10.57? The literature indicates using 1G/gallon twice, and 0.5G/gallon Fermaid K once. That doesn't seem to be nearly enough. I'm working on that. 

By the way, great video... the graph is outstanding to me and visually explains a lot.


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## Ajmassa (Dec 29, 2020)

David Violante said:


> Thank you gents, this is a lot of good information. I do tend to overthink a little, perhaps because I also want to truly understand. You know... dive in and swim under water a little before coming up for air. At some point you get to actually swimming when you combine the understanding and the experience.
> 
> @Ajmassa I think your experience is a great example. @dmw_chef here is the manual from Vinimetrica, it indicates you need either their unit or a pH meter that goes out to 2 decimal places.
> 
> ...



See?! This is what happens when ya start diving into YAN and additions based on known levels. You open up an entire world of confusion! Light years away from my comfortable “1g per 1gal” dosing! lol

Scott’s Labs seem to be really pushing FermaidO. Personally i’ve always avoided it unless making an addition later in the ferment. Anyway if you dive into that handbook (which is extremely beneficial. thank you for posting that) they basically say YAN from FermO is weighted. So you wouldn’t need to compensate 200 actual ppm but more like 40ppm. They are calling it “YAN Equivalent” . Allegedly 10ppm of FermO is actually 40-60ppm equivalent. Yet DAP & FermK “measureable” YAN & YAN equivalent are unchanged. 

It’s super detailed and they really are in love with their Fermaid O it seems but i feel perfectly comfortable still using DAP and FermK for my nutrients—especially if my YAN level clocks in low. Not sure how extensive the research was but they only site one study within that handbook regarding this. As if all of this wasn’t already somewhat confusing Scott’s Lab decided to create entirely new terms (measureable YAN & YAN equivalent) to shill FermO. It’s like they want all to fall in line with FermO & pretend any other way is now wrong. 

*(After living through 2020 it’s difficult to not be skeptical or question things— like this hard shift to FermO from Scott’s Lab while FermK & DAP have worked for so many for so long)


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## dmw_chef (Dec 29, 2020)

David Violante said:


> I'm still working out the math, to actually understand the right additions at the right times (ppm vs g/gall etc...) Ex: 1G/Gallon of Fermaid O is actually 10.57ppm YAN. If I need 200ppm, is the math 200 / 10.57? The literature indicates using 1G/gallon twice, and 0.5G/gallon Fermaid K once. That doesn't seem to be nearly enough. I'm working on that.



There is a spreadsheet linked in the TBE paper; you can take a look at how it does the math.


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## dmw_chef (Dec 29, 2020)

One more tidbit:

Question: 


> I hear a lot of conventional wisdom that excessive YAN supplementation can increase risk of microbial spoilage in finished wine; if I’m reading your answer correctly that is not the case?



Answer from Scott:


> I think that the use of excessive YAN is overstated from a microbial spoilage standpoint as any lees aging/stirring will induce autolysis and that releases nutrients. However, you want to have sensible nutrient regimes (calculations, additions and management; so no excessive) as yeast nutrition is greater than nitrogen and the amount required is dependent upon temperature, pH, oxygen management, etc. If you push nitrogen really high then you need to accommodate with high vitamins and minerals which is challenging as how do you know how much. In addition low nitrogen requiring strains do not perform to their optimum in high YAN environments. A tailored regime is much better.


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## David Violante (Dec 30, 2020)

Ajmassa said:


> See?! This is what happens when ya start diving into YAN and additions based on known levels. You open up an entire world of confusion! Light years away from my comfortable “1g per 1gal” dosing! lol


Yeah... I'm getting to see how complex it can be. It's really interesting though and I'm looking forward to coming up with a solution that I will understand and be very comfortable with, having peeked behind the science curtain. I read the YAN Equivalent component with Ferm-O but want to read through more of their research to better understand why they consider it a much higher equivalent. An important take-away for me is using a testing kit (like in doing SG, pH, TA, etc...) and understanding yeast more. As @dmw_chef and others say, "You take care of the yeast, they get the job done". 



dmw_chef said:


> There is a spreadsheet linked in the TBE paper; you can take a look at how it does the math.


I'll have to check that out. I read through Deezil's calculations and they made sense until they didn't, among the variations of measurements used across the field (ppm, g/hL, gallons, g/L, etc...). I can figure out a complex medication dosage in the field at 2am in the dark and then this is like Ionic Greek. 

Thank you all for your participation down this Rabbit Hole...


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## David Violante (Dec 30, 2020)

@Ajmassa I'm curious about what your nutrient dosing schedule is. It sounds like you're using GoFerm, Fermaid-K and DAP. How much do you use when?


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## jgmillr1 (Dec 31, 2020)

You can measure the nitrogen content using the formol titration method. (Note that this is the same as the Vinmetrica test kits but doesn't run you $32 a pop.) If you have sufficient lab equipment and skills to measure TA, you can also measure nitrogen. This does require the use of formaldehyde which is nasty. I was able to buy it off Amazon though, go figure. It is the only item in my lab space labeled as flammable + poisonous (due to methanol) as well as carcinogenic.

Procedure here:
1) Titrate your 5ml wine sample to pH of 8.2
2) Titrate the formaldehyde you'll use to pH of 8.2 in a separate beaker
3) Add 2ml of the titrated formaldehyde to your wine sample
4) Measure initial volume of 0.01 N NaOH on your buret
5) Titrate to pH of 8.2 and measure final volume on buret
6) N (mg/L aka ppm) = (Vol of NaOH) * (Normality of NaOH) * 14 * 1000 / 5
This simplifies to N (mg/L) = (Vol of NaOH) * 28 if you are using 0.01N NaOH and a 5ml sample of wine.

One caveat, this measures all the Nitrogen not only the YAN, so it tends to over report the actual yeast-usable nitrogen content by upwards of 10%.


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## stickman (Dec 31, 2020)

There are plenty of nutrient suppliers itching to sell you product, in the US you have Scott Lab, Gusmer, BSG, and Enartis to name a few, take your pick. Some information regarding YAN has been changing throughout the years, so you really have to decide what supplier or lab to trust, and use their products based on the current data sheets provided. I've been using Superfood for many years and don't intend on changing any time soon. Reducing the use of DAP is nothing new and has been suggested since the mid 80's as far as I know, probably earlier. The main issue is to not add DAP by itself, as this throws off the organic to inorganic ratio (3to1 typical) which already exists naturally in the must. Unfortunately there are times when the must YAN is so low that supplementing with organic nitrogen alone may not get the job done, so most current information still suggests using DAP combined with a complex nutrient for very nitrogen deficient musts.


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## Ajmassa (Dec 31, 2020)

David Violante said:


> @Ajmassa I'm curious about what your nutrient dosing schedule is. It sounds like you're using GoFerm, Fermaid-K and DAP. How much do you use when?


When 1st figuring this out for myself i noticed that everyone seems to have slightly different protocols. I’ve kept the same routine for the past few years since i started making wines from grapes. It’s based off the morewine guide to red winemaking & advice from the forum.

1. rehydrate yeast with GoFerm
2. 1st nutrient dose at 1st punchdown:
fermK 1g/gal + an extra shot of DAP (around .25-.50g/gal)
3. a few hours later i add my Acti-malo hydrated lactic bacteria & opti-malo nutrient to the must.
4. at 1/3 thru i add my 2nd full dose of fermK 1g/gal

i don’t follow this like gospel though. i’ve skipped the DAP, or the goFerm at times. i’ve added some fermO later. And i’ve butchered that 1/3 timing i admit. But that’s pretty much been my default nutrient protocol comfort zone. The only thing that will change with a known YAN level will be the 1g/gal dosage likely.

*some literature calls for 1 dose of fermK split up in 2 halves. I do 2 full doses as written in that manual and has worked well for me. 

Now your turn! What’s your typical nutrient schedule?


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## dmw_chef (Dec 31, 2020)

I always and without fail use go-ferm to rehydrate my yeast. I firmly believe that of all the nutrients, go-ferm is perhaps the most important as it has minerals and sterols the other nutrients don't provide and are necessary for an optimum ferment. 

I target 250-350 YAN depending on OG and yeast (or higher, my cranberry mel got 450), satisfied with a mixture of ferm-o, ferm-k, and DAP, following SNA (staggered nutrient additions), divided into 4 equal doses at 24h, 48h, 72h, and the 1/3 break. Bear in mind I'm a meadmaker, not a winemaker (I have made a couple accidental wines when a gallon each of syrah, nebbiolo, and moscato juice started to spontaneously ferment in the fridge); however, when I make no-water melomels (fruit, honey, and no additional water) I still do SNA. 

FYI @Ajmassa, your nutrient regime probably adds about 100ppm, counting YAN from go-ferm. Not saying that's good or bad, just supplying information.


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## CDrew (Dec 31, 2020)

I've noticed what the Scott Labs paper says-That a fermaid O suplemented fermentation does not get as hot as the Fermaid K fermentation. But I've used both interchangeably depending on what I have around. In 2020 I tried mostly to use Fermaid O, and dosed 1.5 g/gallon at first punch down, and 1g/gallon at 18 brix. But I think any nutrient protocol is better than none at all. Remember, before 20-30 years ago, plenty of wine was being made and I doubt any of it was being supplemented with anything other than DAP. I feel fortunate we have more options and more science, not that it's perfect. But I do feel that nutrient additions do assure that fermentations go to completion. And since I'm always at the higher end of the brix, its a helpful thing.

For 2021, I'm going to buy a decent quantity of Fermaid O, and use that exclusively. I routinely get fermentations into the mid 80s and want to keep temps in check a bit. During late September and Early October (wine season) temps are often 90F in the day and 60F at night. SO you just have to roll with it.


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## dmw_chef (Dec 31, 2020)

yeah, that's why I do SNA instead of giving huge boluses of nutes tends to keep temps stable even with k/DAP in the mix.


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## David Violante (Jan 1, 2021)

There’s a lot to unpack here! 



jgmillr1 said:


> You can measure the nitrogen content using the formol titration method.



Thank you, I’m going to have to try that. I’ve been better at being able to measure TA but truthfully haven’t done it in the last couple of batches. It’s interesting to see how many people do measure it and how many do not, just relying on pH and taste. Not saying I shouldn’t, there are good reasons to do so. I should get back into the habit.



stickman said:


> There are plenty of nutrient suppliers itching to sell you product, in the US you have Scott Lab, Gusmer, BSG, and Enartis to name a few, take your pick. Some information regarding YAN has been changing throughout the years, so you really have to decide what supplier or lab to trust, and use their products based on the current data sheets provided. I've been using Superfood for many years and don't intend on changing any time soon. Reducing the use of DAP is nothing new and has been suggested since the mid 80's as far as I know, probably earlier. The main issue is to not add DAP by itself, as this throws off the organic to inorganic ratio (3to1 typical) which already exists naturally in the must. Unfortunately there are times when the must YAN is so low that supplementing with organic nitrogen alone may not get the job done, so most current information still suggests using DAP combined with a complex nutrient for very nitrogen deficient musts.



I’ve been using GoFerm, Fermaid K & O mostly because that’s what I was exposed to here. I haven’t really looked at others but it’s probably a good idea just to see what’s out there for perspective. I think you’re right though, finding someone you trust and sticking to it is a good idea. It will take some weight off your shoulders and you can just get on with it all. I hadn’t realized the 3:1 ratio. That makes sense now thinking about what happens when you add just one part of the equation.



CDrew said:


> I've noticed what the Scott Labs paper says-That a fermaid O suplemented fermentation does not get as hot as the Fermaid K fermentation.



My understanding (recent) is that the yeast eat the DAP components like junk food and rapidly proliferate, which both uses and expends energy but which therefore increases temperature. Hence after using DAP in some way the temperature of the must goes up accordingly. To @stickman ’s point, it seems like a balanced nutrient addition is important, and to @dmw_chef ’s point I think it’s probably better to do a step feeding when possible. Especially if the yeast will just nosh down on the DAP, increase in quantity and increase temperature. The video he posted was great at explaining yeast nutrition needs. 

@Ajmassa I’m starting to narrow in on a schedule. At least I have a target now, previously I was shooting arrows into the sky, as it were. I use GoFerm because of it’s nutrient, protective, and startup properties. I like the step approach of adding amounts based on yeast strain and starting SG, at 24, 48, and 72 hours, and 1/3 drop. I like using Fermaid K because it has both nutrients and DAP, and Fermaid O towards the end if sluggish. I will most likely use 1G/gallon for wine and 2G/gallon for mead. I also use pectic enzyme to help with maceration and bentonite to give yeast places to bind and do their thing and to help clear later on. I think I read on here that it also helps with some of the aging issues if using enzymes. I haven’t done anything with malolactic fermentation yet, that’s probably next. I do cold soak as long as possible and I want to try saignee next too.


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## dmw_chef (Jan 4, 2021)

A friend of mine posted a video today about calculating nutrition for superfruit meads, there's a lot of good info in here that would likely be applicable to winemaking too:



Keep watching to the end; he wraps up a couple times


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## Ajmassa (Jan 4, 2021)

dmw_chef said:


> A friend of mine posted a video today about calculating nutrition for superfruit meads, there's a lot of good info in here that would likely be applicable to winemaking too:
> 
> 
> 
> Keep watching to the end; he wraps up a couple times



what is a super fruit mead?


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## dmw_chef (Jan 4, 2021)

Ajmassa said:


> what is a super fruit mead?



Honey, fruit, and no additional water.


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## Rice_Guy (Jan 4, 2021)

This is an excellent video for general purpose “rules” on fermenting. Thanks for posting


dmw_chef said:


> A friend of mine posted a video today about calculating nutrition for superfruit meads, there's a lot of good info in here that would likely be applicable to winemaking too:



_the calculator which the video references:_








Personal YAN Nutrient Calculator 2.1


Sheet1 SG,Yeast Nutrition Reqmt,Offset PPM,Brix °,Sugar g/L,Instructions 1.085,Medium,18,20.5,222, ,1. Enter must Specific Gravity. (A2) 2. Select Yeast Nutritional Requirement. (B2) 3. Optionally, enter an Offset PPM to reduce the Target YAN in A5 (C2). 4. Enter batch size in gallons (B5) 5. S...




docs.google.com


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## David Violante (Jan 9, 2021)

Apologies about the silence, it has been ridiculous at work with COVID. I’m finally sitting down with a cup of coffee and reading through the posts and catching up.

@dmw_chef thank you for the video, it is super helpful. I tried using the online calculator, and it seems to work online but when I downloaded a copy the syntax of the cell calculations didn’t transfer. Ex: instead of (x-y) the formula says (x minus y). For some calculations I could figure it out, but for some I couldn’t. I emailed the author and he related he wasn’t really good at excel. Any suggestions?


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## dmw_chef (Jan 9, 2021)

are you using it in google sheets?

tryjng to use it in excel is probably a bad idea.


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## David Violante (Jan 9, 2021)

Works completely fine in google sheets. I thought I saw thst he wanted us to download a copy. I only have google sheets on my iPad. Was using excel on my desktop to try and use it.


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## dmw_chef (Jan 9, 2021)

David Violante said:


> Works completely fine in google sheets. I thought I saw thst he wanted us to download a copy. I only have google sheets on my iPad. Was using excel on my desktop to try and use it.



Just make a copy using your google account


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## sour_grapes (Jan 9, 2021)

I will admit that I was surprised to see how incompatible the functions of google sheets and excel are.


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## cmason1957 (Jan 9, 2021)

I have sometimes had good luck with Libre office and Google spreadsheets, but not always. And then you can sometimes take it from Libre office to excel. I'll see if I can get this to work tomorrow.


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## cmason1957 (Jan 10, 2021)

I did try and Libre Office was quite happy with the spreadsheet, but wouldn't convert it into something that Excel was happy with. It can probably be done, but it will involve hand conversion.


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## David Violante (Jan 11, 2021)

Thank you for trying... looks like it’s by hand then...


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## wekv (Oct 6, 2022)

jgmillr1 said:


> You can measure the nitrogen content using the formol titration method. (Note that this is the same as the Vinmetrica test kits but doesn't run you $32 a pop.) If you have sufficient lab equipment and skills to measure TA, you can also measure nitrogen. This does require the use of formaldehyde which is nasty. I was able to buy it off Amazon though, go figure. It is the only item in my lab space labeled as flammable + poisonous (due to methanol) as well as carcinogenic.
> 
> Procedure here:
> 1) Titrate your 5ml wine sample to pH of 8.2
> ...



Hey JG & all - I'm new here (been making wine from home grown grapes for ~7 years now.) I'm trying to up the ante every year and get more self-reliant on testing (w/o all the gizmos) this year in lieu of spending $60+ per panel of testing on each sample at the "local" university extension. I do like to know the YAN and have a keen interest in chemistry (loved it in college) and still remember a lot.

Looking at the above test (which is great to know) I see you make use of 0.01N NaOH in the lower half of the protocol. What is the Normality of NaOH that you use to titrate out the 5ml sample (line 1) and Formalin (line 2)?? I would think that matters since a greater titrant normality or concentration, say 0.2N, would not dilute the titrand (sample & Formalin) as much and affect the chemistry in the 2ml sample (line 3).

Also, I saw this test protocol from Brewing Forward wiki (a similar procedure):

Check pH of formaldehyde and if not at pH 8.0 neutralize with 1N NaOH
Clarify the wine sample with a 5μm syringe filter or equivalent.
Transfer 10.0 mL of the clarified sample into a 25-mL volumetric flask. Bring to volume with deionized water, and mix well.
Transfer a 10.0 mL sample of the clarified and diluted wine into a 30-mL beaker, place calibrated pH/reference electrodes and a stirbar into the solution, mix, and adjust the pH of the sample to 8.0 with 1 N sodium hydroxide.
Add 2.0 mL of the previously neutralized formaldehyde (pH 8.0) to the aliquot, mix, and titrate back to pH 8.0 with the 0.05 N NaOH.
The concentration of fermentable nitrogen is given as follows:
Fermentable Nitrogen (mg N/L) = (mL of 0.05 NaOH titrated) x 175

Notes[1]

Formaldehyde is carcinogenic and a bronchial irritant, so handle with proper ventilation.
The pH of formaldehyde gradually shifts downward. Its pH should be checked and readjusted to 8.0 prior to each use.
The Formol titration only titrates one nitrogen of arginine, it also titrates approximately 14% of the proline present. These two errors are, at least, partially offsetting.


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## Ajmassa (Oct 6, 2022)

wekv said:


> Hey JG & all - I'm new here (been making wine from home grown grapes for ~7 years now.) I'm trying to up the ante every year and get more self-reliant on testing (w/o all the gizmos) this year in lieu of spending $60+ per panel of testing on each sample at the "local" university extension. I do like to know the YAN and have a keen interest in chemistry (loved it in college) and still remember a lot.
> 
> Looking at the above test (which is great to know) I see you make use of 0.01N NaOH in the lower half of the protocol. What is the Normality of NaOH that you use to titrate out the 5ml sample (line 1) and Formalin (line 2)?? I would think that matters since a greater titrant normality or concentration, say 0.2N, would not dilute the titrand (sample & Formalin) as much and affect the chemistry in the 2ml sample (line 3).
> 
> ...


Even tho it feels like it should be a fairly standard test it seems that overwhelming majority of people don’t test for it and use just a standard nutrient protocol. plus some distributors will even supply YAN levels with their fruit.

so it’s a pretty niche topic and I don’t recall speaking with anyone who ever actually utilized that YaN kit on this site.

you Are in unchartered territory my friend. Godspeed.


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## Ajmassa (Oct 7, 2022)

wekv said:


> Hey JG & all - I'm new here (been making wine from home grown grapes for ~7 years now.) I'm trying to up the ante every year and get more self-reliant on testing (w/o all the gizmos) this year in lieu of spending $60+ per panel of testing on each sample at the "local" university extension. I do like to know the YAN and have a keen interest in chemistry (loved it in college) and still remember a lot.
> 
> Looking at the above test (which is great to know) I see you make use of 0.01N NaOH in the lower half of the protocol. What is the Normality of NaOH that you use to titrate out the 5ml sample (line 1) and Formalin (line 2)?? I would think that matters since a greater titrant normality or concentration, say 0.2N, would not dilute the titrand (sample & Formalin) as much and affect the chemistry in the 2ml sample (line 3).
> 
> ...





I just went back and looked into the testing process using the reagent kit I will be using. And it’s actually super simple (When sticking with just one set of instructions) 

Basically it’s just testing for TA.
Add formaldehyde to the sample.
test again. 
Do math. 
Get YAN!

Everything using the “TA titrant” from Vinmetrica. It’s .13N. Im pretty sure that’s interchangeable with .1N. But using multiple NaOH’s ? I will avoid that at all costs. .05N .1N, .2N, 1.0N — it all just confuses the hell outta things. So I’m gonna keep the default at .1N (or 0.13N) just to make everything easier 

Though Vinmetrica site even on the same page has contradicting info from instructions to video. And also on neutralizing the formaldehyde. Instead of 8.0ph the manual says “looking for ph to be between 6.5 and 8.5ph“ Or to even just go by color change. Idk man. 

Below is what I gather to be the most straight forward method. I’m sure when I get around to it there’ll be some learning curve Just like any other lab work. 




Set up for a typical TA test but using a 10mL wine sample instead of normal 5mL
Add another 10mL of distilled water 
Perform TA test to 8.2ph endpoint. Set sample aside 
neutralize the formedehyde you’ll be using (2mL/test required) to 8.0ph by adding NaOH one drop at a time. (Only needs a few drops)
Add 2mL of neutralized formaldehyde to the already titrated sample and mix 
Ph will drop and then perform TA test again to 8.2ph endpoint. Note mL used. 
Take the mL used from the 2nd formaldehyde test * 0.1333 * 1400 = YAN mg/L


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