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2010 October 12

The confusion over using yeast nutrients continues, and for good reason.  Mostly lack of information about the grapes a winemaker has to deal with is the biggest problem.  As I have said here in the past getting YAN numbers on the East Coast in a timely fashion is almost impossible and very expensive.  At the moment there are no simple tests that a winemaker can purchase as there are so many others for all types of parameters.  The two tests that need to be taken are Ammonia Content and N-opa.  The resulting figures are added together to arrive at YANC (content)  Armed with this information a winemaker can make a much better determination at arriving at a protocol  that will do two important things. One provide enough nitrogen to keep yeasts healthy while keeping to a minimum the amount of inorganic nitrogen in the form of Diamonium Phosphate (DAP) added to the Must.

In attempting to arrive at the correct amount we also have to look at how the additions are made.  The staging is just as important as the amount.  When we look at the fermentation kinetics we want to achieve, the correct staging becomes even more important.  Greg Perrucci , Winemaker said  the following with regard to longer lag phase yeasts, “A long lag yeast like BM45 or AMH leaves the window open for a wild strain to do some of the work before they take off. Unless that is your desired outcome, having DAP in the must only makes that more of a problem. The same goes for damaged or diseased fruit. Adding DAP can give bacteria some easily accessible food source to accelerate their spoilage.”

It is probably safe to say adding too much nutrient at the beginning can have a negative effect by encouraging a wild strain of yeast to have an effect on the Must.  And we understand that nutrients containing DAP or DAP alone cause a quicker fermentation.  Whether it is stylistic or the benefit of a slower start and a quick finish results in eliminating residual sugar, it is clear that the answer is a product like Fermaid O.  It can be used 24 hours prior to pitching yeast without fear.  With regard to the YAN content for Fermaid O it will add 16 mgN/L at a rate of 30 g/hl  We can add that to our already known number we received from our YAN tests.  And  unlike Fermaid K it can be added if necessary at 10 brix.

Here is what we know.  Go ferm will add 10ppm, Fermaid O will add 16ppm, Fermaid K will add 25ppm, and Dap will add 60ppm all at a rate of 30 grams per HL except the Fermaid is at a rate of 25 g/hl any more exceeds the TTB Limits for Thiamin.  We also know for a Must with a Brix of 25 we should have a YAN number of 300.  So if we make one addition whether we split it or not, and we should, at 1/3 depletion we can add 111ppm of Nitrogen.  That is great, except we have to have an original YAN number of 189 to get to 300.  Now I am sure that the 300 number is not hard and fast. I am sure it should be used as a guide.  But nevertheless it is a benchmark.

OK, so now you don’t do YAN tests. So what do you do?  You probably should assume you have a YAN of 150 to begin with.  If you look at the old formulas developed for using DAP and Fermaid K additions. They added up to about 150ppm and that added to the assumed 150 got us to 300.  So we were pretty safe.  Then the DAP FEAR SYNDROME hit.  It’s junk food, it’s terrible, it ruins wine, don’t use it and on and on.  And so the Trendoids stopped using it altogether.  But in doing so they lost the potential for 60 ppm with no way of getting it from another source.  So everything was cool until you had unknowingly a low YAN Must and then you got the STINK or the STUCK.   Here is an example posted on that other forum,

“ I have 1080# of a merlot-heavy bordeaux blend (merlot, CS, CF). All 36# lugs from CA. Merlot from Caterina vinyards in northern CA, = the rest are calif. special (CV fruit). Using BDX yeast. around 13-14% ABV potential. ph adjusted to 3.66 (didn’t have to go far). Cold Soak for 2 days with lallazyme EX and 1.5# med toast american oak chips. Rehydrated BDX with go-ferm, added small amounts of must over the next half hour, innoculated at must temp ~ 60°f. Added booster rouge, and opti-red. Things went very well first 2 days. Day 3, H2S smell, SG around 1.068, time to add Fermaid K (~1/3 sugar depletion). 3 punchdowns daily, fermentation temps right around 80°F, still, a slight but noticeable H2S smell. What gives?

What gives? If you have been reading this so far it should become obvious. No Fermaid O , No Fermaid K at the establishment of the cap , and no consideration of using DAP. Might I offer LOW LAN as a reason?

Here is some really great advice from Greg,” The biggest reason we are switching to less DAP up front is to better control the ferment. Lab isolates are relatively aggressive and we like the ferment to start slower and finish stronger. With too much DAP early on, it is harder to control a runaway ferment. Some of them have dropped 50% in 24 hours which makes it hard to add more DAP at that point without potential problems going into MLF. Most of those fast starters die down quickly and take several days to clean up the last bit of sugar. With the addition of non-DAP nutrients, the yeast still have Nitrogen, just not much of the ammonium form of it. Ferments started with non-DAP nutrients take off slower and then shift into high gear when we add the DAP. They heat up a little more in the end and finish the last of the sugar almost overnight.”

You will notice that the use of DAP is not eliminated. It is just when it is added is what is important. With some discussion and research I have come to the conclusion that the best strategy for a LOW YAN or UNKNOWN YAN Must is the following.  I would use only yeast with a short lag phase not a long one, even if the long one brings out special wild Gooseberry flavors.  Go Ferm is a given in any situation.  An addition of Fermaid O to the Must 24 hours before pitching if cold soaking or just before if not.  A ½ addition of Fermaid K at the onset of Fermentation (cap established) the second half at 25% depletion and at 1/3 depletion the DAP addition based on fermentation speed and temperature.  IF sluggish at 10 brix, I would consider an addition of Fermaid O. By doing this we think we can achieve what Greg said here,” What we have found is that if we add too much DAP early and not enough later, the ferment is more at risk of H2S and not going dry. If the additions are reversed, the results are always clean and dry.”

Since we are keeping the additions to a minimum it is also a good idea to use yeast hulls after the fermentation start, it adds no nitrogen but it absorbs toxins. And the use of Opti Red or Booster Rouge is also a benefit.  It was a bit scary I will admit, but knowing the YAN number of this year’s Pinot Noir we did not use any DAP and half the Fermaid K.  You can read about the details of that ferment here. At the end of the day without knowing the YAN content it is probably prudent to take a middle of the road approach.  Assume 150 ppm and add the 111 ppm.  That means some minimal use of DAP. Get over it already, unless you are a Trendoid .  Like most Trendoids you probably are only making 6 gallons anyway.

27 Responses leave one →
  1. OneCarboyJoe permalink
    October 13, 2010

    Yes, I only make one carboy of wine a year. I do a saignee, delestage, pump overs with punch downs and a submersed cap. I separate the free run from the press wine. Geez that is a lot of work! Maybe I will buy a WinePod for about 20K and then I can make 10 gallons of wine.

  2. Gene Fiorot permalink*
    October 15, 2010

    You should also consider Penis Enlargement Therapy. Heck , Why not? from the looks of it you could probably use whatever you can get.

  3. RSG permalink
    October 16, 2010

    Gene, you shouldn’t kiss and tell…LOL

    Seriously, the comment about the wine pod is hilarious, Wonder why it never took off……..LMAO?

  4. Rod Wintle permalink
    October 17, 2010

    Looks like I have a “text book” example here for Gene. I have 7 cases of Sangio that I am about to start. I am using BM45 (I was not aware of BM 4×4 at the time).

    At this time, I have ~27 gallons of must and anticipate ~17.5 gallons of wine.

    I will use Go-Ferm to rehydrate. 12 hours later, the must will get a dose of Fermaid K (18 grams in 360ml of water)

    At 20 BRIX, the second does (18 grams and 360ml of water) will be added to the must.

    Then, finally, we will add 17 grams of DAP at 16 BRIX.

    As insurance, I will place an order for Fermaid O to have on hand just in case :-).


  5. Gene Fiorot permalink
    October 17, 2010

    My only comment is I would use half the total Fermaid K if using I were using Fermaid O. But I would stage the addition timing exactly this way using the DAP with an Unknown YAN content and especially with BM45 .

  6. Rod Wintle permalink
    October 19, 2010

    I missed the 16 mark! Added second dose of Fermaid K at 8am today at 20 BRIX. Arrived home from work at 12.5 BRIX.s

    Too late for my DAP addition?


  7. Gene Fiorot permalink*
    October 19, 2010

    Too late for DAP but don’t worry you will be fine leave it alone. But if it gets sluggish which I doubt at 10 brix you can add fermaid O, Yeast hulls wouldn’t hurt anything now and help prevent problems. Also an Opti red addition would not be a bad idea IF you start to smell something off.

  8. bzac permalink
    November 14, 2011

    I guess I must be one of those trendoids .

    My default protocol is to hydrate with go ferm , use an SIY like nobless or optired in the must , add fermaid O at end of lag phase, ie first signs of a cap forming and add fermaid K at 1/3 depletion .

    And have some dap on hand if I detect any signs of H2S , which is why I don’t use a refractometer for my fermenting wines, I like to really evaluate the big sample a hydrometer requiers , taste smell etc.

    I’ve even had good success with using fermaid O for the first and second additions with my washington fruit , but again keeping DAP on hand as an intevention if needed , so far I haven’t needed it.

    I do this because I want to control the speed of the ferment , have a lower peak and not have any residule YAN in the wine that could end up fodder for Brett.

    Most people I encounter who have H2S issues related to nutirtian have them because then don’t use any nutirents , not because they used fermaid without suplimental DAP .

    If I was working with super ripe 28 brix california fruit or underripe finger lakes fruit where I could assume a very low natural YAN I might have DAP as part of my protocol rather than as an intervention , but working with 24 brix 6.5 ta 3.6 ph BC and washington fruit , I haven’t needed it.

    I think it all depends on what your goals are and the fruit you work with . I don’t use DAP normaly but am not dogmatic about it , its one of the arrows in my quiver.

  9. Gene Fiorot permalink*
    November 14, 2011

    Hey Zac you found this posting. LOL You give very good advice here on this subject. Every winemaker should be aware of what you are saying. We pretty much follow the same path. Fermaid O has made a big difference in the way we go about it. We are going to go a little slower on the 2011 Cab then we did with the Merlot.

  10. Bzac permalink
    November 14, 2011

    I like some of the long lag phase yeasts , provided a 50 ppm so2 addition was added . This will stun the wild yeast some what , and give you a little cold soak and let the enzymes do their thing a little longer s the must warms up.

    They also seem to cope with living on the natural yan well , so you can get a nice linear curve in your ferment,

    Different strokes for different folks , my approach is that if I can eliminate dap I will.
    Organic forms of yeast are more easily metabolises by yeast so you can have a healthy ferment at lower total yan numbers.

    Again the goal being to ensure residual yan levels are as low as possible lowering your spoilage risk .

  11. Linc permalink
    February 2, 2013

    Thanks for the extremely informative discussion Gene. Sorry I’m late to the party but I just found out about the site a few days ago. I have two questions. The first is, when you say you add DAP (or not) at 1/3 sugar depletion “based on fermentation speed and temperature,” can you clarify what speed and temperature would cause you to add DAP and which wouldn’t? Also, how (if at all) would would you adjust your regimen based on the nutrient requirements of the specific yeast strain you are using (i.e. high vs low). Thanks. Linc

  12. Gene Fiorot permalink*
    February 2, 2013

    To answer your second question first, I would say I work very hard on avoiding yeasts with high nutrient requirements. However if you are using a high nutrient yeast and do not have YAN test results or worse you have a low YAN grape it makes it hard to avoid DAP to get to a proper level of nitrogen especially if you have a high Brix Must. There are limits to Fermaid K you can add and Fermaid O does not add that much nitrogen to the total.

    As far a speed and temperature there are so many variables involved. First is ambient temperature then the volume of must creating heat and the length of the fermentation you desire. For example if you have an under ripe grape to avoid vegital flavors it is a good idea to ferment hot and quick. Certainly adding DAP at 1/3 depletion will add to the heat and speed of the fermentation. On the other hand if you are looking at a 14 -21 day ferment of a Cab Sav while you still would like a nice heat spike you are not looking to be done quickly. Lot’s of nuances here to consider which not only come from reading but experiencing multiple ferments to really get a handle on it.

  13. Linc permalink
    February 2, 2013

    Thanks Gene…definitely need (and hope) to experience multiple ferments in the not too distant future…

    I decided that the primary goal for my next ferment is to ensure that it ferments completely dry…my last 3 stopped at 0 brix, and although I didn’t test for residual sugar I suspect there a little bit still in there. Will definitely reread this blog before starting the next one.

  14. Gene Fiorot permalink*
    February 2, 2013

    A clinitest can determine RS if you are concerned. Using an inexpensive hydrometer is not always a good indication. You should have a plus 5 Brix Minus 5 Brix Hydrometer. This will allow you to read below zero. However you will find some wines go lower than others depending on alcohol content. Also after pressing if you keep your wine warm when you begin MLF you will also complete the sugar fermentation as well.

  15. Gene Fiorot permalink*
    February 2, 2013

    Also I should say the premiere recognized Amateur Winemakers in the hobby post on this blog. Wading through bad advice on other forums is not a problem here. Ask away and I am sure you will get good advice from the contributors here.

  16. crazy run ranch permalink
    February 4, 2013

    I have never added DAP as a practice, only as a response to a stinky fermentation above 10 Brix. I did test for YAN or YANC for a couple years and did not find knowing these values to provide me with useful information. I had problems with must with good nitrogen numbers and had smooth sailing on some with very low YAN. So I’m not convinced that low nitrogen is always the cause of H2S production. If it was, we could easily turn this into a nitrogen math problem and never have problems again.

  17. Gene Fiorot permalink*
    February 4, 2013

    Well Scott Labs sure made it a Math Problem that’s for sure!

  18. Bzac permalink
    February 4, 2013

    I think the type of nitrogen is a factor too
    I went to a Lallmand workshop and their research indicates that organic nitrogen is easier for the yeast to metabolise than inorganic forms of N so you can have a successful ferment at lower YAN absolute numbers

  19. Gene Fiorot permalink*
    February 4, 2013

    One thing is this topic of nutrients is always in flux and always a challenge for winemakers. I have tried mostly Inorganic Ferments, all Organic Ferments, and mixed but greatly reduced Inorganic additions with Organic nutrients. My feeling is I sweat too much the All Organic and I am very comfortable with a mix. In any case the wines are better with using less DAP than more. I do love the YAN tests when they are available. Beckstoffer and Lanza have provided them to us and that makes it easier to avoid or use less DAP.

  20. Dan Lodico permalink
    February 4, 2013

    I didn’t get any YAN numbers this year for Beckstoffer or Lanza. did you?

  21. Gene Fiorot permalink*
    February 4, 2013

    Not this past year from either. We were promised them as in the past but the season was crazy for Rick Lanza and Berton Costamagna. No excuses for next year fellas!!!!

  22. Anatoli permalink
    June 17, 2013

    I started calculating required nutrient amounts for my must and I got numbers which are somewhat larger than Fermaid-K and Fermaid-O recommended dose from Lallemand.
    For instance if I need extra 150 ppm in 5gal/19L of wine. If I to take Fermaid-K which should contribute 100ppm/g/L, then I’d need to add 1.5g/L or 28.5g for 5gal. However advice from Lallemand is to use 5g/5gal, which is 26.3ppm.
    Any advice on my dilemma? Am I missing something here?

  23. Gene Fiorot permalink*
    June 17, 2013

    Well you have arrived at the point where sometimes the Chemistry and Reality don’t jive. First the limitations on Fermaid are due to TBB regulations concerning limits on Thiamin. Not exactly a proven problem but it exists. Since you are not commercial you can ignore to where you are comfortable. While the numbers are supposed to add up many times as you site you can’t seem to get enough. The best way I know is to utilize Go ferm Protect to begin. Then Fermaid O and Opti Red at onset and Fermaid K at 25% sugar depletion along with a tannin addition as well as SIY yeast cells then or at 10 brix. Then if sluggish another Fermaid O addition at 10 Brix. By sluggish I mean less that half the brix being divided in a 24 hour period at 16 brix. If you are really fearful a normal dose or less of DAP at 25% depletion is nothing to worry about. Without YANC tests you are ball parking and that is what we all do 75% of the time.

  24. Anatoli permalink
    June 17, 2013

    thank you for your answer, it’s pretty much what I did. I was just concerned with a suspicious smell at the beginning of ferment, but with 40ppm DAP it was gone, I followed normal nutrient additions afterwards. What do you do with recommended YAN then, keep it in mind as a guideline if ferment goes out of ordinary?

  25. Gene Fiorot permalink*
    June 18, 2013

    First it is high doubtful you have H2S at the beginning but you could have a smelly ( nail polish smell) wild yeast that will be taken over as soon as the cultured yeast takes command. As I said you have to monitor your temperature and brix drop off. If you are gaining temperature from 18 to 10 brix then you probably will complete without problem. Of course you have to also be aware of the yeast type you are using. For example GRE will give you a quick rise and faster drop in that range than BDX or MT. So you have to get accustomed to a yeast’s performance as well when you are evaluating your fermentation. But Smell is the key and if worse came to worse and you were a bit stinky at 10 brix a little DAP or Fermaid O could be the answer with another SIY Yeast Cell addition. I think it is better to ferment with the same yeast to get to know it as opposed to switching yeasts every batch without any base line experience. There is always time to introduce a new yeast to your experience base.

  26. Anatoli permalink
    June 18, 2013

    I thinks you are right, Gene, as soon as cultured yeast took over, the smell was gone. I can’t say it was nail polish. Just something I am not familiar with. perhaps I mixed it with burn rubber, so I freaked out a bit.

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