About

Techniques in Home Winemaking is a resource for home winemakers looking for information or help on making great wines, and to share that knowledge with fellow winemakers. This resource is based and builds on my book by the same title. Much of my experience is derived from extensive literature search as well as from my experience both as a home and a commercial winemaker. Click here if interested in ordering a signed copy of my book.

Share

1,115 thoughts on “About

  1. Daniel Pambianchi

    Hi Burak,

    I was referring to the wine phases, both the liquid phase and the vapor phase, which comprises all the gases above the wine surface that exist in equilibrium with the liquid phase. Those will be primarily water and ethanol.

    Keeping wine at 20C is not good for aging. It accelerates aging via oxidative processes and also favors microbial spoilage. Are you not able to cool down the area using something like an air conditioner?

    And you are correct, it can be very difficult to inhibit an active MLF with a small dose of KMS; it’s the same with yeast though bacteria are more sensitive. Once the MLF is complete, you only need an amount commensurate with the wine pH as per my calculator; you also need to move the wine to cooler storage.

    To inhibit MLF, you would need a larger dose (75-100 ppm), filter the wine down to 0.45 um to remove as much bacteria as possible, and move it to cool storage. This is what I do when I want to stop an active AF and want to keep residual sugar; I also chill the wine down to 6-8C.

    If you cannot sterile filter the wine before bottling, you will need to treat with lysozyme and KMS as the wine is microbially instable.

    Good luck

    Daniel

    Reply
    1. BURAK TUNA

      Hi Daniel,

      thankyou again, now my mistakes are clear to me. I will try to do like you advise.

      Nowadays, i have been trying to make my sulphite knowledge deeper by re-reading your book and your other publications.

      In this blog, you had informed somebody named Mike : Infrequent large sulphite additions are more effective than frequent small additions. As an example i understand like this, first we measure the current level, then find the must be level acc to pH. We enter these data in your calculator and it gave us a result for example 5 gr but, we put the double 10 gram. I understood this logic like this. Is that right ?

      Today i viewed your so2 management protocol from 2014 ( couldn’t completely read) , a pdf doc. In the last page 11, you say “As is recommended by enologists, making small additions regularly is more effective than large infrequent additions”

      Could you please illuminate the thing, which approach i have to follow up ?

      Salute

      Burak

      Reply
  2. Daniel Pambianchi

    Hello Burak,

    Some winemakers will still recommend smaller and more frequent additions. The argument is that you maintain the recommended free SO2 level at all times.

    Quite coincidentally, soon after my 2014 study, some new research and a new book was published in 2014 by renowned enologist Jacques Blouin where he made a strong case for larger and less frequent additions. The biggest advantage of this strategy, which I now support and recommend, is that you end up adding less sulfite throughout the life of the wine during maturation, and that you end up with a lower Total SO2.

    The challenge is determining what adjustment factor to use. This depends on the style of wine and its chemistry. I provided some guidelines in the notes following the online Sulfite Calculator.

    For example, for whites I suggest a 0% adjustment factor. For a full-bodied red, I suggest 100% early on and then gradually move down to 50% and 33% on subsequent additions. These would be infrequent and not every 3 months as is done with the other regimen. I would say measure your SO2 and do the additions when the free SO2 level reaches the recommended level based on pH but WITHOUT the adjustment.

    For example, if your pH is 3.25, the calculator recommends 14 mg/L free SO2 at 0% adjustment and 0.5 mg/L molecular SO2 for a red wine. So double that amount on your first addition, at the end of the MLF. Monitor free SO2, and when it hits around 15 mg/L, adjust SO2. If it’s a full-bodied wine, use 100% again, otherwise, you can move down to 75% or 50%. Then monitor and measure free SO2 again, and when it hits 15 mg/L, add sulfite again with maybe 50% or 33% adjustment, and repeat on the final racking using likely just 0%.

    It takes a bit of experience to master this technique. I measure total phenol content in my wines, and so I was able to master it fairly quickly. Yes, my wines have higher free SO2 levels, but I bottle at the recommended level (i.e. with 0% adjustment), and that results in lower Total SO2 then the other strategy.

    I hope this clears it up.

    Daniel

    Reply
  3. Seth

    Daniel-
    I have taken note of your reply to my query in November (hadn’t been notified via email) and truly appreciate it. Also apologize for the familiar Dan vs. Daniel. Won’t make that mistake again.
    I have now gone back and read your blog for the past year. I find it wonderful that you give so generously of your time and knowledge. Thank you!

    I have made 2 seasons of Cab S/Merlot blends and am now on my 3rd. All from grapes shipped from Lodi to upstate NY. Questions further to cold soaking:

    1) Please expand on the pros and cons of pre AF cold soaking and post AF cold soaking. I was wondering if the alcohol provides any benefits in a post AF soak (reduces microbial taint etc.)? We have a club where we perform a crush for the first group (various varietals in 20-40 gal batches), ferment, then press, then crush for a second group etc. Each session runs around 7 days depending on ambient temps and I have been lucky to participate int he first group. I believe the grapes sit in the fridge of the distributor rather than a second shipment from Cali. I thought I could either:
    a. Crush, kill the native yeast with MBS, and take some must home in 2 7 gal pails, put them in a frig covered, for a week or so, maintain 40 degrees, punch regularly, then raise the temp when the first group presses, ferment, and then press with the second group; or
    b. Crush, kill the native yeast with MBS, ferment, and then prior to press, remove and take some must home in 2 7 gal pails, put them in a frig covered, for a week or so, maintain 40 degrees, punch regularly, and then press with the second group.

    I also have a private question with regard to a potential equipment concept, and would love it if you would consider emailing me personally.

    Thanks again for all you do.

    Seth

    Reply
  4. Daniel Pambianchi

    Hi Seth,

    You have to check the box below the COMMENT box to receive notifications. Know that I respond very quickly, usually well within 24 hours. So if you don’t receive a notification, go see if I responded because I likely did.

    The main benefit of pre-AF cold soak is to extract anthocyanins (color pigment molecules) as these are more soluble in juice (absence of ethanol). And the main benefit of post-AF cold soak is tannin integration (via polymerization), which gives a smoother mouthfeel. The alcohol doesn’t protect the wine from microbes; you really need to chill it down and protect it with CO2 or other inert gas. Alcohol in wine can actually lead to chemical oxidation and/or microbial spoilage if not protected.

    Yes, your techniques for processing and cold soaking are good. If you have a freezer with lots of space, you can also freeze crushed must; that actually helps extract more color. The freezing and thawing process ruptures grape skin cells, which causes further release of anthocyanins.

    Hope this helps. You can email me at daniel@TechniquesInHomeWinemaking.com

    Cheers,
    Daniel

    Reply
  5. Seth

    I had checked the box…

    Thanks for the speedy reply.

    I will follow your advice. No freezers, and since I don’t control the timing of the press, I will go with pre-soak at 40 degrees (unless you think colder is better).

    No gas so I will keep the head space limited in the buckets?

    Any suggestions in terms of number of days? Again, our club crushes once, ferments an average of 6-9 days, then press, and then crushes the next day all over again. So I could go 6-9 days of pre-soak and then 6-9 days of fermentation as needed.

    Thanks again.

    Seth

    Reply
  6. Seth

    I had checked the box…

    Thanks for the speedy reply.

    I will follow your advice. No freezers, and since I don’t control the timing of the press, I will go with pre-soak at 40 degrees (unless you think colder is better).

    No gas so I will keep the head space limited in the buckets?

    Any suggestions in terms of number of days? Again, our club crushes once, ferments an average of 6-9 days, then press, and then crushes the next day all over again. So I could go 6-9 days of pre-soak and then 6-9 days of fermentation as needed.

    Thanks again.

    Seth

    PS- No notice this time either, and it seems to give you an error when posting, have to hit back, and then repost.

    Reply
  7. Seth

    I had checked the box…

    Thanks for the speedy reply.

    I will follow your advice. No freezers, and since I don’t control the timing of the press, I will go with pre-soak at 40 degrees (unless you think colder is better).

    No gas so I will keep the head space limited in the buckets?

    Any suggestions in terms of number of days? Again, our club crushes once, ferments an average of 6-9 days, then press, and then crushes the next day all over again. So I could go 6-9 days of pre-soak and then 6-9 days of fermentation as needed.

    Thanks again.

    Seth

    PS- No notice this time either, and it seems to give you an error when posting, have to hit back, and then repost.

    I have tried to post this several times, here is the error:

    al error: Uncaught exception ‘phpmailerException’ with message ‘Invalid address: (setFrom) admin’ in /home1/daniel17/public_html/blog/wp-includes/class-phpmailer.php:1023 Stack trace: #0 /home1/daniel17/public_html/blog/wp-includes/pluggable.php(352): PHPMailer->setFrom(‘admin’, ‘Techniques in H…’, false) #1 /home1/daniel17/public_html/blog/wp-content/plugins/subscribe-to-comments/subscribe-to-comments.php(845): wp_mail(‘ron@ferraro.us’, ‘[Techniques in …’, ‘There is a new …’, ‘From: “Techniqu…’) #2 /home1/daniel17/public_html/blog/wp-content/plugins/subscribe-to-comments/subscribe-to-comments.php(789): CWS_STC->send_mail(‘ron@ferraro.us’, ‘New Comment On:…’, ‘There is a new …’) #3 [internal function]: CWS_STC->send_notifications(69567) #4 /home1/daniel17/public_html/blog/wp-includes/class-wp-hook.php(300): call_user_func_array(Array, Array) #5 /home1/daniel17/public_html/blog/wp-includes/class-wp-hook.php(323): WP_Hook->apply_filters(”, Array) #6 /home1/daniel17/public_html/blog/wp-includes/plugin.php(45 in /home1/daniel17/public_html/blog/wp-includes/class-phpmailer.php on line 1023

    Reply
  8. Daniel Pambianchi

    Yeah, it’s a WordPress error and I don’t know why. I’ll need to look further into, but rest assured that you’re messages are being posted, so no need to try again.

    A cold soak of 7-10 days or even 14 days if you can manage it is ideal.

    Reply
  9. BURAK TUNA

    Hello Daniel,

    do we have a data how much TA and pH change during alcoholic fermentation (AF) for red wines and
    how much tartaric and malic change as TA change during AF ?

    Greetings

    Reply
  10. Daniel Pambianchi

    Hi Burak,

    That’s an impossible task because there are so many factors that come into play. There is juice chemistry (which itself depends on variety, vintage, viticultural practices, etc. etc.), yeast strain selection, fermentation dynamic, etc. etc.

    Some yeast strains are able to metabolize malic acid into lactic acid, so that can change TA significantly.

    In general, you can expect TA to increase (assuming there is no change in malic conversion) due to the production of succinic acid during the AF, and therefore the pH to decrease.

    Daniel

    Reply
    1. mike m

      Hi Daniel ,
      Now that the MLF is complete on my red wine, I added SO2 and wondering if I should rack the reds and transfer the wine to a new glass carboy? I used the Vinmetrica SC50 unit to test for malolatic acid .
      Thanks Mike

      Reply
      1. Daniel Pambianchi

        Hi Mike,

        You should have racked AND THEN added the SO2 (assuming you are not doing sur-lie aging), but ok. In 3 months, rack again, check/adjust the SO2 level. Rack and adjust SO2 every 3-6 months.

        Daniel

        Reply
  11. Kathi Jo

    Hi Daniel

    So, what are the primary advantages of fermenting at cooler temperatures?
    I am using R2 from Scott Labs for my pressed frozen Frontenac Gris. Making dessert wine. One carboy did not start at all ( 2 did). This has never happened before. Gave it over 34 hours, but seeing zero action in the air lock and only a very small amount of bubbles. R2 temp range is 41 degrees F to 80. I think 🤔 I may have let there be too much of a temp swing from soaking in Go Ferm to inoculation. The juice is at about 60 degrees. The cocktail of GF and yeast was at about 75 degrees. The only other difference is that the non- starter is in a glass Big Mouth Carboy, the other 2 are in narrow neck glass containers. I reinnoculated at 65 degrees, but wondering if I should raise the temp

    Reply
    1. Daniel Pambianchi

      Hi Kathi Jo,

      Fermenting at cooler temperatures for whites and rosés helps retain the delicate aromas — that’s the main reason.

      It is absolutely critical that the yeast culture be properly acclimatized before inoculating the juice. That means you shouldn’t have a temperature difference of more than 15°F (8°C). So add a little juice (say, 10 mL) to the yeast suspension ONCE IT HAS STARTED FROTHING, wait a few minutes, then add a little more juice, and continue in this fashion until the temperature of the yeast culture is within 15°F (8°C) of the juice. When the yeast is ready, add it to the fermenter.

      It seems you were within this range, but it sounds like it might have been borderline; it definitely would have helped to acclimatize the yeast just to avoid such problems.

      Give it another 24 hours; it should start. R2 is a bayanus strain, so I’m sure it’ll wake up soon and get to work.

      Good luck.

      Daniel

      Reply
      1. Kathi jo

        Hi Daniel
        I ended up restarting the BiG Mouth Carboy with another inoculation of R2….this time with tightly controlled temp. After over 48 hours the air lock remained absolutely still. I was worried that the juice was going to spoil. Was thinking maybe the Big Mouth container top was leaking air…resulting in a quiet air lock. There were a few bubbles at juice surface, but nothing like the other 2 carboys. I wrapped the top in Suran Wrap…still no motion. I then transferred that juice into a narrow neck glass carboy and within a few hours it was bubbling away. What the heck? Not understanding the science behind this.
        Your thoughts?

        Reply
        1. Daniel Pambianchi

          Hi Kathi Jo,

          I’m puzzled as to what’s happening.

          The only plausible explanation is that there is a leak around the Big Mouth closure or bung. Maybe there is a defect in the lid liner or the lid is simply not sealed properly, or maybe there is a leak between the bung and airlock.

          You should test this by pressurizing the Big Mouth just a little with CO2, or start a fermentation in some water and sugar solution to create CO2, and then submerge the Big Mouth completely under water and check for leaks.

          Also check for any hairline cracks in the airlock; it can happen. It happened to me once and I caught it a bit too late, and my wine had suffered slightly. If the sulfite solution in the airlock is levelled when it shouldn’t be, like during fermentation, it is a good indicator that there is a problem with the airlock if everything else is fine.

          Good luck.
          Daniel

          Reply
          1. Kathi Jo

            Thanks Daniel
            I think you are right. There must have been a leak in the container or airlock. The good news is it was probably slowly fermenting all that time. I just could not see it. It tastes fine…still very sweet as it should be. I may actually add some acid back in. My TAs and malic acids were really low this year…..for Minnesota. Even this Frontenac Gris was 1.1. My Marquette was .93 with a Malic Acid of 3.2. This is almost unheard of in Minnesota. It was a good year for me on my south facing, limestone hill. : ).
            I wish the Minnesota Grape Growers Assiciation would have you speak at the Cold Climate Conference this March. We could all learn from your vast knowledge.

            Merry Christmas to you and your family. So grateful for your guidance in all matters…of wine

            Peace & Joy
            Kathi Jo

          2. Daniel Post author

            Hi Kathi Jo,

            Yes, that’s the good news … the wine was likely fermenting all along.

            I’m confused about your acidity numbers. Looks like you are using both %age and g/L numbers. Your Frontenac’s TA seems to be 1.1%, or 11 g/L, but then your Marquette seems to be 0.93% but your malic is 3.2, which would be in g/L. Are you saying your Marquette’s TA is 9.3 g/L with 3.2 g/L of malic? That would make sense and, yes, unusually low for Minnesota. Who tested TA and malic acid levels?

            Yes, I would be interested to do a seminar at the MGGA.

            Merry Christmas to you and your family too.

            Cheers,
            Daniel

          3. Kathi Jo

            Hi Daniel

            Yes. I move my decimal point around a bit. I am finding that some folks in the wine world use “10” interchangably with 1.0 depending on who I am reading or talking to. The juice was sent to ETS Labs the day after I picked the fruit. I keep it refrigerated until I ship it, then send it with an ice pack. This year I used a relatively new product from Scott Labs on my vines. It is called Lal Vigne (sp) An inactive yeast that you spray on vines a few times. It tricks the vine into thinking it is under attack by a yeast/mildew. This causes the vine to speed up maturation ….in theory. It is tough to use here because it has to stay dry for a few days after application. We had lots of rain. I had purchased it for my 2016 season but because of my cardiac arrest I ended up dropping all my fruit to the ground that year. I gave some to a friend that provides Frontenac for me. We treated a few rows with it and some without. I processed both. side by side using exactly the same steps. There is a profound difference in the taste of those two wines. I never ran any chemistry on them so I am not sure where they started. I will send to ETS before I bottle them. It is only 5 gallons of each , so have not wanted to spend the big bucks. Because of the big taste difference in those two, I ordered more for 2017 including the one used on white wines as well. I am not sure if this product contributed to my great numbers this year or if my vineyard has just matured and is now able to really represent the environment. 2017 was year 7. My vineyard sits on a south facing hill in a retired limestone quarry. It is about 10 degrees warmer than the surrounding area. Also the open pit of the quarry floor fosters a steady breeze which I think helps cool them off in the evening. We also had an early start on the growing season this year as we had our last frost in the end of April rather than mid May. My malic acids are usually between 4.5 and 5.5. TA is usually between 1.1 for Marquette and 1.7 for the Frontenac varieties. I will continue us to use the Lal Vigne and maybe I will leave a few vines un-sprayed to test the difference

          4. Daniel Post author

            Hi Kathi Jo,

            I find it best to use measurements with units instead of percentages; it’s a lot clearer and avoids confusion. Percentages are well understood in winemaking, but if you start talking about concentrations of reagents, solutions and additives, then % becomes confusing since you don’t know if what is meant is % by weight (%w/w), % by volume (%v/v), or % weight to volume (%w/v). You did it again when going from talking about malic levels (4.5 and 5.5 g/L) to talking about TA (1.1% and 1.7%).

            Yeah, you have many factors there that can profoundly change grape chemistry at harvest. You are in a challenging climate with having to deal with such high TA levels … 17 g/L!!

            Good luck
            Daniel

  12. Seth

    Daniel-
    Hope you are enjoying the Holiday Season.
    Speaking of cooler temps for whites and Rose’s etc:

    1) 2016- I had pulled some juice off saignee from Cab Merlot for Rose, and although it tasted great, there was an onion background on the nose?
    2) 2017 – Did the same for Merlot only, and while very young, I note a similar although lesser nose.

    Thoughts?

    Seth

    Reply
    1. Daniel Pambianchi

      Hi Seth,

      Just about getting ready for the holidays.

      I’m not clear at what stage the juices/wines are at. An onion smell points to a problem from hydrogen sulfide (H2S) or another thiol, or possibly even disulfides. But these would typically originate from fermentation problems or from leaving the wine on the gross lees for too long, hence why I’m not clear. I would not expect to get those smells in juice.

      Try a light racking to see if the smell dissipates, otherwise you can try a copper or Reduless treatment. This should take care of H2S, if that’s the problem. It can be difficult if the problem is disulfides.

      Happy Holidays
      Daniel

      Reply
      1. mike m

        Hi Daniel,
        now that my red wine is finished with MLF , racked and sulfated , should I stir the small amount of lees 3 times a week?
        Thanks Mike

        Reply
        1. Daniel Pambianchi

          Hi Mike,

          Yes, though if you racked, you do indeed have very little lees. In the future, you can stir during the MLF but ever so gently so as not introduce excessive oxygen that might otherwise inhibit the LAB, or, sulfite (not sulfate) without racking.

          Cheers,
          Daniel

          Reply
      2. Seth

        Hope your weekend was wonderful.

        Sorry for not being more clear. The Onion nose was only after bottling last year, and this year, it is there, less detectable, but still there, after AF.

        Thoughts and actions?

        Thanks
        Seth

        Reply
        1. Daniel Pambianchi

          There can be a number of reasons why you are getting that smell. It can be from the type of yeast you use, maybe from a stressful fermentation (such as insufficient or even too much of nitrogen), maybe wine sitting on the gross lees for too long, or vineyard sprays that have been applied too close to harvest.

          In the bottle, the phenomenon is known as “reduction,” which basically means that the sulfur compounds are manifesting themselves in the absence of oxygen. For reds, this is part of the reason why it is important to aerate them during the early stages of winemaking. Wines bottled under screwcaps are known to exhibit this reduction because the closures allow almost no oxygen to enter the bottle compared to natural corks. This is why some sommeliers will tell you to decant even a bottle of white under screwcap, just to get rid of the reductive smell.

          If you notice this type of smell during winemaking, try a light racking, and if that doesn’t work, you will need to treat it with a copper sulfate.

          Good luck.
          Daniel

          Reply
  13. BURAK TUNA

    Hello Daniel,

    my first question is on the malic acid. Mike Miller at Accuvin says that malate concentration can run from 4 – 6.5 g/L in grapes from cool climates, to 1 – 2 g/L in musts from warmer climates. So, can we conclude like this : A MLF will be not necessary for a grape harvested at 25-26 Brix in a warm climate (like napa) considering the very low malate content ?

    Second question is about pectolytic enzymes Rapidase AR2000 you informed in the book. Doug Moorhead from Piwine classifies this as aromatic enzymes and says that they are not much effective except in grape varieties with higher levels of the monoterpenes such as Riesling, Sauvignon Blanc etc. which all of are whites. What do you think, whether we have to use this for reds considering a bentonit treatment afterwards is necessary ?

    Third question is regarding cold stabilisation (CS). You say that a CS won’t be necessary, if our cellar is higher than 15°C. That means tartarates still precipitate between 4 and 15°C slowly and fewer although the cellar temperature doesn’t decrease till to <4°C, am i right ?

    i wish you merry christmas

    Reply
    1. Daniel Pambianchi

      Hello Burak,

      Thank you for the Christmas wishes. Wish you too a very Merry Christmas.

      #1. Those are common malic acid levels, yes, but I’ve seen those at much higher and much lower concentrations. There are other factors beyond cool and warm climates that affect malic acid production and concentration in grapes. Even if malic acid levels are low, they are still a source of microbial instability; that means the malic acid needs to be dealt with properly or it may cause an MLF or other lactic acid spoilage in bottle.

      #2. That’s correct, I only use Rapidase AR2000 in aromatic whites (Muscat, Gewurz, Riesling, etc) to release the aroma compounds from their binders, namely, sugar molecules. It is generally not recommended in reds as that cleavage reaction would make sugar-bound anthocyanins that much more unstable.

      #3. Wine is only tartrate stable to the lowest temperature it was stabilized at. What I wrote, as you state, is that if your cellar temperature never goes below 15C and you don’t expect the wine to be stored at cooler temperatures EVER, then that’s ok; it’s ok if you control how the wine is stored and serviced for consumption. If you give a bottle to a friend and they place it in the fridge and leave it there for even a couple of days, tartrates will form. Therefore, if you make wines for others, and as a general precaution, I always recommend to cold stabilize the wine. Even if you stabilized the wine down to -10C (like I did once on a commercial Icewine prior to bottling on mobile line), tartrates will form if the wine is subjected to colder temperatures (like it happened to my wine left overnight in an unheated barn because the pickup truck did not show up; the temperature fell to -20C). I will change the wording in a future edition. Thank you for asking for this clarification.

      Cheers,
      Daniel

      Reply
  14. BURAK TUNA

    Hello Daniel,

    it is very nice to hear from you that a new publish will come, we’re waiting for it !

    In the new edition, please kindly add the clarification that aroma enzymes are generally not for reds. I already added the aroma enzyme in my red wine :))

    Secondly, you can add the figure 2 in the page 4 of Mike Miller’s acids presentation (pdf doc in the following link), which is a very helpful picture explaining what the pH and TA are.
    http://www.gencowinemakers.com/docs/Acids%20Presentation.pdf

    My last question in this year :)) is regarding batonnage. You wrote that in some cases, batonnage is being made till one year after AF.
    That means; following AF we make only the first racking to remove the gross lees and don’t cold stabilize the wine at the same year with AF. Meanwhile, we make batonnage each week during one year and don’t make any racking/-clarification treatment. After one year, we’re racking + clarification and then cold stabilising, is that right ?

    Why this confused me, becuase i cannot imagine how to differenciate the precipitated tartarates and fine lees in the sediment in the carboy, as long as i make batonnage.

    Salut
    Burak

    Reply
    1. Daniel Pambianchi

      Hi Burak,

      I don’t when a new edition will be out, but that would be the plan.

      Yes, I already noted to specifically mention in the new edition that aroma enzymes are not for use in reds.

      I will look into including a figure like Miller’s that better explains acidity and pH, sure. That’s a good illustration.

      Cold stabilization should always be the very last step before bottling because, until then, you don’t know what else you’ll be doing to the wine that may alter its tartrate stability. For example, you may decide to add another (not tartrate stable) wine and create a blend, which would require to re-stabilize the wine if you had done it already.

      Correct. When you are doing with bâtonnage, you would rack again, perform any fining operation you desire, and then cold stabilize. Some winemakers also choose to rack between the fining operation and cold stabilization, but that’s not necessary; it also causes more oxygen uptake. You should be able to distinguish the difference in aspect and texture between fine lees and tartrate crystals.

      Cheers,
      Daniel

      Reply
  15. mike m

    Happy new year Daniel,
    I plan on using oak sticks in my 5 gal. carboys of red wine from grapes–2017 vintage, and at present Iam stirring on the lees and wondering if its ok to add the oak after the lees stirring process of one year is over ?
    Thanks Mike

    Reply
    1. Daniel Pambianchi

      Hello Mike,

      Thank you, and a Happy New Year to you too.

      You can add the oak sticks at any time, really. My own recommendation is to add them as early as possible to then let the oak and tannins integrate sooner in the wine and with the other wine substances.

      Daniel

      Reply
  16. mike m

    Hi Daniel,
    Since my white wine does not have any lees after 3 rackings should I continue to stir it several times a week and run the risk of exposing it to oxygen?
    Thank you for your advise, Mike

    Reply
    1. Daniel Pambianchi

      Hi Mike,

      If there are no more lees, what is there to stir?

      In lees stirring, you stir the fine lees for whatever duration you like/want, but it has to be on the whole lees volume, i.e. no racking.

      Daniel

      Reply
  17. BURAK TUNA

    Hello Daniel,

    my question is regarding D-LAB. Accuvin offers a test kit to determine it.
    For instance, i have two different wines and found out the D-LAB content in one wine as 30-75 mg/lt and 75-200 mg/lt in the other one by using the test kit.
    For these two wines, how will we able to calculate the SO2 and Lysozyme addtitions ? Is there a tool for this ?
    Have a nice day.

    Reply
  18. Daniel Pambianchi

    Hello Burak,

    The D-LAB kit is used to determine the amount of residual LAB in wine. If the wine has gone through 100% MLF, i.e. there is less than 50 mg/L residual malic acid, a sulfite addition immediately following completion of MLF is all that is needed — there is no need for lysozyme.

    Lysozyme is needed when there is residual malic acid, anything above 50 mg/L though some use 100 mg/L., and is added at a rate of 20-30 g/hL in conjunction with sulfite (it absolutely needs to be added with sulfite) independent of the amount of malic acid. Sulfite is added based on pH. Alternatively, you can sterile filter the wine.

    Daniel

    Reply
  19. Dan Ashburn

    Hello, Daniel, and Happy New Year. It has been a while since I contacted you and much has happened over the past year or so – including making a lot more wine.
    I am helping another wine maker on some larger volumes of wine and we are looking at finishing, fining and bottling some late harvest Semillon. The current acid level is 9.45 g/L and, after doing some taste tests, we decided to increase it to 10.5 g/L. The addition part of it is easy, but we have a disagreement on what type of acid to use.
    Based on your book and many of the articles I’ve read on acid adjustments, I suggested using straight tartaric acid, although I was O.K. with using a 60/40 mix of tartaric and malic acid. My friend wants to use just malic acid and citric acid, as he believes any tartaric acid will precipitate out since there was a good amount of tartrates on the tank bottom after cold stabilization. This generates two questions.

    First, after cold stabilization, if we want to increase TA back up, would any added tartaric acid just precipitate back out or would it remain in solution?
    Second, I have read several articles regarding using citric acid and the concerns about microbial stability and – my over repeated concern – potential for acetobacter. Almost everything I have read has stated that any acid additions to grape wine should be tartaric and/or malic acid and to stay away from citric acid.

    Your thoughts?

    Dan

    Reply
    1. Daniel Pambianchi

      Hello Dan,

      Thank you and a Happy New Year to you too.

      Tartaric acid is generally the acid of choice for any adjustments because, in addition to being the most significant in grapes and wine and therefore the most “natural”, it is also the most stable. But the issue of stability is really only pertinent in wines that have been or will be subjected to a malolactic fermentation (MLF), usually mainly reds.

      But if you have already cold stabilized the wine, you would need to stabilize it again if you add tartaric acid.

      Please note that it is not tartaric acid that precipitates but, rather, potassium bitartrate (KHT). In wine, a temperature-dependent equilibrium exists among potassium bitartrate (KHT), and bitratrate (HT-) and potassium (K+) ions. Bitartrate are ions of tartaric acid. So if you add tartaric acid (H2T), you would shift the equilibrium towards potassium bitartrate, which would precipitate at colder temperatures. KHT formation also depends on many other wine chemistry factors, such as ethanol concentration, presence and concentrations of complexing factors including polyphenols, proteins, sulfates, metal ions and polysaccharides, such as pectins and gum arabic. These wine compounds can bind with tartaric acid or potassium and bitartrate ions and reduce the availability of these ions to form and precipitate KHT.

      Back to the issue of stability of other acids and your second question.

      Any wine that has residual malic acid is considered at risk of microbial spoilage. Commercial wineries make use of sterile filtration to remove yeast and bacteria that could otherwise cause unwanted microbial activity. The greatest risk is that of lactic acid bacteria (LAB), which would feast on malic acid. If sterile filtration is not possible, only high levels of sulfite or a combination of lysozyme and sulfite can keep LAB in check. “Good” LAB are responsible for MLF and the many pleasant substances they produce, but bad LAB can also metabolize malic acid into spoilage substances. And both good and bad LAB can metabolize citric acid into objectionable levels of diacetyl and acetic acid; that’s why adding citric acid is never a good idea. Acetobacter (acetic acid bacteria or AAB) is not implicated in malic metabolism.

      Personally, I would add tartatic acid and cold stabilize again. If you cannot cold stabilize, you can add a protective colloid, such as carboxymethyl cellulose, yeast mannoproteins or potassium polyaspartate.

      Good luck!

      Daniel

      Reply
      1. mike m

        Hi Daniel,
        My Chard. wine finished MLF and I will add sulfite and wondering if I should rack it now or wait?
        Thanks Mike

        Reply
        1. Daniel Pambianchi

          Hi Mike,

          The important thing is to sulfite ASAP based on your wine’s pH. You can either rack BEFORE sulfiting or you can sulfite and then leave the lees in and stir for whatever period of time you desire for a richer taste.

          Good luck!

          Daniel

          Reply
          1. mike m

            Hi Daniel,
            The ph of my chard wine is 3.45 so I added sulfite to equal 80ppm. I checked the ph the next day and it was only 20ppm! To be sure all equipment and supplies were ok, I did a cross check on DI water and the ppm of sulfite checked out ok. I immediately added more sulfite to the wine and it checked out ok. I will check it again today. Do you know why the first addition of sulfite became bound up so quickly?
            Also if I choose to leave the lees in, how frequently do you suggest I stir and for how many weeks should I keep the lees in the wine. At present the wine is stored at 55F.
            Thanks for your help, Mike

          2. Daniel Post author

            Hi Mike,

            With a pH of 3.45 and a molecular SO2 of 0.8 mg/L for a white wine, you need 36 mg/L (ppm) of free SO2 according to my calculations.

            I assume you meant you checked the “free SO2” level the next day, not pH.

            Was this wine aged in oak? If so, there will be a little binding and also some consumption from polyphenols but not to the extent of dropping 60 mg/L in one day. It could be that you have some other binders in there if the wine has any acetaldehyde flaw. Does the wine smell and taste ok?

            Did you process the wine (e.g. racking) after the sulfite addition? Any oxygen uptake will consume SO2.

            Other than that, there may have been a problem with your addition, perhaps you didn’t measure something correctly even though you checked everything; it happens.

            You should measure total SO2 too so you can get a better idea of what could have happened.

            It’s up to you how long you want to leave the wine on the lees and how often you stir. It’s a matter of taste. Try stirring once a day for week, taste, see how you like it, and repeat until you hit your sweet spot.

            Good luck.

            Daniel

          3. mike m

            Thanks Daniel for your reply;
            I did make a mistake in stating ph for ppm of sulfite. I checked the free SO2 today and its ok at 60ppm after the second addition of sulfite. I have no oak in the carboy, however, will add some oak sticks today. The wine smells and taste ok. I will stir the lees once a day and taste weekly.
            Thanks again for your help, Mike

          4. Daniel Post author

            You should measure total SO2 to understand what happened. You need to figure out if SO2 was consumed or if it had become bound.

      2. Dan Ashburn

        Thank you, Daniel. Since we would not have time to cold stabilize again after adding tartaric acid, I lost the argument for adding just tartaric acid. We ended up adding Malic (90%) and Citric (10%) to get the TA up to 10.5 g/L and we will cross-flow filter and sterile filter prior to bottling tomorrow to eliminate/reduce the chance of microbial spoilage. An option that may be available to us in the future is utilizing a Laffort product called Celstab that is used for stabilization and prevents the formation of potassium bitartrate. Are you familiar with this product? Would it allow us to add tartaric acid to a white wine and eliminate the concern for the tartaric acid just precipitating out again?
        As always, your advice and counsel are deeply appreciated.

        Reply
        1. Daniel Post author

          Hi Dan,

          Yes, I’m familiar with Celstab; I use it. As per my earlier response, you can use it for tartrate stabilization as it comprises carboxymethyl cellulose (CMC).

          Daniel

          Reply
  20. David L. Hull

    Daniel, I have your book Techniques in Home Winemaking and have made sparkling wine with dialysis tubing per your article Sparkling Wine, MD. I have searched far and wide and cannot locate the answer to my question regarding the addition of dosage. I’ve made cranberry wine and have them bottled with dialysis tubing now carbonating. I want this wine to be a bit sweeter than it is and want to add a dosage. I’ve made some cranberry syrup and have determined that 20 ml per bottle would be adequate for my purposes as far as sweetness goes. So, the big question: after extracting the dialysis tubing with the yeast content, if I add the syrup to the carbonated wine and stopper it, am I building a bottle bomb? Should I also add some sorbate to each bottle for stabilization? I note your caution that sorbate can cause the geranium smell. I don’t see that you advocate the addition of sorbate in the dosage but you do indicate sulfite and metatartaric acid might be added. This issue isn’t explained much that I can find. Perhaps I’m not looking in the right place?

    Thanks!
    Dave

    Reply
  21. Daniel Pambianchi

    Hi Dave,

    The amount of dosage to add, which really pertains to the amount of sugar, depends on the style you want to create, what you like. So you should perform bench trials with a sugar solution or syrup that you want to use.

    If the wine is not properly stabilized, then yes, it can be a bottle bomb if there is any amount of residual sugar. Usually, just the high amount of of CO2 (osmotic pressure) is sufficient to keep any remaining viable yeast from refermenting. Typical pressure is 6 bars, about 90 psi. If it’s much lower than that, it add to the risk.

    Then , you should definitely add sulfite as added insurance and also to protect against chemical oxidation. No need for sorbate. Metatartaric acid (or a similar protective colloid) can be added to inhibit tartrate formation in case you had not stabilized the wine. I don’t add any as I cold stabilize my wines. I do add gum arabic, which help with tartrate stabilization, increases perlage (CO2 action) and add mouthfeel.

    Cheers,
    Daniel

    Reply
    1. David L. Hull

      Many thanks for that advice, Daniel!

      I guess I still don’t grasp the dosage section of your Sparkling Wine, MD article for Winemaker Magazine where you say that the sparkling wine can be sweetened after removal of the dialysis tubing. That is what I was intending to do but fear the bottle bomb development. Would it be ok to add 20 ml of Wine Conditioner which already has sorbate in it? I know you said that there is no need for sorbate and that osmotic pressure usually is sufficient to prevent re-fermentation.

      The cranberry wine cleared naturally and was racked twice. There were no visible residue and the SG was 990, dry as it could be. Cranberries being what they are, the wine is a bit tart. I was hoping to modify that tartness a bit by the addition of a sweet dosage.

      Dave

      Reply
      1. Daniel Pambianchi

        Yes, you can add a wine conditioner. I’m assuming that you fermented in good Champagne-style bottles that can resist high pressure.

        Reply

Leave a Reply

Your email address will not be published. Required fields are marked *