Discussion in 'General Wine Making Forum' started by 4score, Sep 9, 2018.
I've been reading about oxygen in wine for many years, it can do some good things and also some bad things, it's like stepping into a black hole of information.
Thanks for the link @4score. @stickman is right, this article is almost overwhelmingly dense with info.
Must holds 5mg/L oxygen
Wine holds 7mg/L oxygen
It takes 4mg SO2 to remove 1mg oxygen.
Wine loses SO2 at a rate of 5mg/L (cool months, topped off) to 20mg/L (warm months, head space).
Wine absorbs oxygen at a rate of 20mg/hr/ft^s. So if I have a 23L batch in a bucket 16" in diameter. at 5mg/L wine oxygen capacity, a surface area of 1.4ft^2, and an uptake rate of 20mg/hr/ft^2 at rest, my must in theory is saturated with oxygen in 4.1 hours.
Yeast needs 10mg/L oxygen, and since must is saturated at 5mg/L at crush or after short period of air exposure, "yeast requires little additional oxygen to complete fermentation."
Oxygen uptake can be estimated by using SO2 measurements.
There are some interesting calculations of SO2 requirements at bottling.
I have quite a few "issues" with this paper.
First of all, it has no references. We are just suppose to "believe" every number and claim there is correct. Sorry, too much on the web today is unreliable, I need a solid reference else I will dismiss it. Other details like the author's expertise or CV is not listed may be minor, but it matters. And this is posted at an amateur wine making web site, which is not in of itself a problem -- amateurs can often have a passion that make their knowledge surpass even professionals -- but because it still lacking any of the pre-mentioned references that does put it more into that "Hm" column for me.
Second, the author uses an appeal to idiots argument in his example of transferring wine and O2 effects. The conclusion was to use a larger pump. Well.... duh. And you don't need O2 calculations to indicate that. If you have a 750 gallon vat, you don't use a 150 gal an hour pump unless you are an idiot. Even ignoring the O2 issues. After the first hour everyone but an idiot would be saying, "why am I wasting 5 hours of my life on this, I need to get a large pump". Seriously, I just bought a pump, and it was the smallest capacity in its class, and it is 450 gal an hour pump. And my largest vat is currently 50 gal. A 150 gal an hour pump if fine for 20 gal tanks and carboys. But not for much else. Use the right tool for the right job is a truism in any field or endeavor.
Third, I quote from the paper
Yeast requires oxygen early in the fermentation process to reproduce new cells. Most yeast strains need about 10 milligrams of oxygen per liter to produce a large, healthy yeast population. ....... Saturated juice at room temperature contains 5 milligrams of dissolved oxygen per liter, so yeast requires little additional oxygen to complete fermentation.
So yeast needs 10 milligrams to be healthy, but it only then needs 5 milligrams to "complete fermentation". So at 5 mg there is enough O2 to complete fermentation, but the yeast will not be health? Which is it? There is a clear and obvious discrepancy that the paper does not clarify. There is a reason many wineries pump their must up and over to keep it aerated. Think about that before taking this article at face value.
Forth (et al) -- there are other issues I have, but enough for now.
In short, even if what this paper claims is true (but without references, we don't know), this entire paper still fails as a prime example of ambiguous statements leading to potentially variable interpretations and generally terrible didactics.
That's not what he said. I took it to mean that yeast needs 10mg/L for healthy fermentation, you already have 5mg/L at crush, the yeast needs 5mg/L more, "little additional," to complete a health fermentation. You might cut him some slack; he's a research scientist and physicist by training, and influential enough to have a wine competition named after him. That doesn't make him right, but he's not some slacker commenting on a Facebook post.
But on that note, I was wondering - if yeast needs 10mg/L for healthy fermentation, and the must gets saturated with 5mg/L at crush, what happens when you hit that must with SO2?
The paper may be of interest on a scientific level but the paper fails to make practical application of the authors assumptions.
Without that, the majority of home wine makers and perhaps even wineries are left with a vague and ambiguous set of statements
Do wineries make all these detailed measurements? There are few statements about how long it takes for the stated exposure numbers to occur. Granted there are a few but it's not complete. Most such reports include statements about how tests were conducted.
Overall the article, while interesting, lacks recommendations for practical application of the 'findings.'
I got good takeaway, confirming what has been written before:
Wine quickly and readily absorbs oxygen
It takes a long time for the oxidation reaction to occur once the wine is saturated oxygen
SO2 quickly removes oxygen
Big takeaway: "Proper SO2 management is a major deterrent to oxidation"
I quoted him. That was exactly what he said.
And I indicated how someone else, who is not you, might take it to mean something else. That was my point by poor didactics. It allowed too much interpretation due to ambiguity. And equally, even if you don't think it is ambiguous, does not mean everyone agrees with you. All this then adds to a potential for individual confusion. And thus is potentially a disservice.
If he was, as just one example an auto mechanic as his day job but a brilliant amateur wine maker, your point to cut him some slack would have merit. But if he is a research scientist he should know the proper way to write even a white paper, so as to provide and show the source of real facts and knowledge with even some generic source citations -- the authors citation of himself at the barest minimum (because not everyone may circulate around his elite circle). Citations also allow for an appropriate baseline for debate. So he should know better and even more reasons why I will then absolutely not cut him any slack. He is writing something that even a beginner will read. It should still be properly referenced and not just dispensed as dogma just because he has a "wine competition named after him"**.
**A logical fallacy sometimes known as an "appeal to authority". That is nice for him he has such a recognition. But..... It may only prove he has a following. Won a popularity contest among others in his peer group who have a narrow world view but one they can all agree upon. That does not prove in any way he is "right", or there are not other options. Popularity means nothing regarding facts. A real scientist would agree with that. Lets see the references. Let's see the actual science based source of the claims. That is all I ask. Seeing those, I may agree. Till then, this paper means nothing on it's own to me.
You quoted him. Then you paraphrased him and built your strawman. Nice job.
Man your horse is high.
Great read! A few more takeways
161 mg oxygen saturation capacity for an "normal" 6 gal batch of wine(and it only takes hours)
280mg of oxygen in a liter of air
That means a headspace of about only about half a liter(161/280=0.575L) can saturate the wine. Ouch :/ That makes me think that anything I've heard about reducing surface area in a fermentation vessel is totally useless, and it's all about headspace volume and kmeta, especially kmeta. This really gave me a better understanding of how important kmeta is and how it can fix/scavenge dissolved oxidation days or sometimes even weeks after the fact since the oxidation reactions are pretty slow. Hence the interesting advice that if you need to splash rack, splash the daylights out of it and kmeta, because it's going to be saturated and it's safer to do it right the first time than baby it and have to repeat. Likewise a popped bungs or dry airlocks are no big deal as long as you've got good kmeta levels and don't let it go long enough(days) to burn through all your kmeta.
I asked renowned author Daniel Pambianchi to review the article. He said, "I'm very familiar with this article; it's a good article. DO in a fully saturated wine, though, is more like in the 8.0-8.5 mg/L range. It is not non-trivial given that that extra 1.0-1.5 mg/L of O2 chews up an extra 4.0-6.0 mg/L of SO2. I discuss all this in my seminars."
Step into the oxygen black hole if you like. There is a lot of good information here. There are so many factors involved, this is why general wine making procedures have been adopted over the years, and long before the technology became available to make these kind of measurements. This is interesting to me, and may be interesting to some or may turn off others, but really we just want to make wine we like.
Thanks for sharing this. Seems like my “theory” of o2 tolerance during aging from early exposure holds some water after all.
Hey @balatonwine - you’ll be happy to know these reports cite multiple references. They appear detailed and professional.
I challenge you to dissect these and point out flaws if any. I bet you can’t do it!
—-lololol ahhhh. Just joking man. Pls don’t actually do it.
It put me to sleep. I'm happy with my plastic bucket full of yeast gasping for oxygen. I did not know they were suffering and I doubt they are aware either. I just want to make wine, not write papers. Sounds ultra simplistic, I know. But, the reality is there is very little we in our micro wineries can do to change. Add O2? How much is good? How much is too much? How much will the instruments to measure it cost? I just follow the good practices I learned here...stir daily, then airlock, watch the head space, bottle and store as best I can. I like the results.
But....I've never been a numbers guy.
Stickman & Mismost - I agree. Such reports are great for those looking for the newest fine details of how to make wine and have limitless time and funds to 'perfect' their methods.
Unfortunately most of us simply need clear and SIMPLE guidance on the do's and don'ts of wine making. Investing another $100.00 or more to read how much oxygen is in my wine is pointless to me and most home hobby wine makers. Fine for those making 50 gallons of wine at a whack and commercial wineries. For the rest of us give us the plain and simple facts, tips, guides that we can apply day-to-day.
Here's a similar practical example from my days in the military. The manufacturers of a fighter jet and a munitions company sent engineers to airbases to work side-by-side with the guys and gals who service fighters and load munitions. I believe it was called Project Blue Suit and here are 2 examples:
Engineer - "Son - according to the tech manual you should be opening this door to access that engine adjustment point."
Airman - "Yes sir, but I can't get my tool in that door as easily and safely from THAT door but I can do it from here and it takes fewer fasteners to remove and replace this panel because I can do this other adjustment too.
Engineer - Scratches his head and then steps away to make a phone call - telling the tech manual folks to fix that tech manual.
Engineer from Munitions Company - "Well how's it going today? Any problems arming and loading these bombs?"
Munitions Loader Airman - "Well no problems sir but one thing makes our job difficult in keeping track of the fuses for these bombs. You see sir the bombs come on pallets with 10 to a pallet. BUT the fuses come in boxes of 12. Every time we arm up these jets we have fuses left over and the numbers don't match up to the bombs left on a pallet. We have to account for all of them and it's a real pain."
Engineer from Munitions Company - Steps away and makes a phone call to the plant and loudly makes it known that the packaging and shipping of their bombs and fuses has to change NOW.
It's all about practical steps. You can give me all the technical info you want but if it's not in practical terms I can use... It's not likely to do anything but frustrate me. Sometimes practical application of scientific facts is impractical or so difficult as to make the job ugly. AND if the real world impact of it all isn't really critical, maybe it's not THAT important. Tell me how long is too long to leave a wine in a fermentation bucket once it finishes fermenting. Give me numbers and methods I can use. Give me solutions when you tell me there is a problem. Give me Risks vs Benefits so I can make a realistic choice best for me.
Farming looks mighty easy when your plow is a pencil and you're a thousand miles from the corn field. (Dwight D. Eisenhower)
That’s kinda my point. To not put too much worry into it. I don’t get into all the specifics either. Or references. Life’s too short. My mindset has always been open ferments, and to not fear o2. And I believe part of that PowerPoint got into the idea I had that early exposure to o2 during fermentation benefits the wine later on— making it less susceptible to browning from o2 exposure during aging.
Why go so far out of your way to make a point that it’s not practical info for small scale makers? Thats already understood. But that DOESNT MEAN ITS NOT BENEFICIAL TO KNOW** —and certainly no harm in discussing.
I don’t have the means for many things in winemaking- but still find it interesting.
And many people do make large volumes or own small wineries on WMT. Maybe this info helps them. Maybe they know some comparable techniques that could help us smaller scale makers. Who knows?!
But instead of discussing the findings and potential techniques we could do—-we are discussing why the info isn’t relevant? Or trying to poke holes in a report’s references or math- but not the subject itself? Why? This is a damn winemaking forum!
If I don’t find a thread’s topic to be relevant for me, then I just simply skip over it
Well said, AJ. Yes, lots of people here are not the target audience for some of these documents. Doesn't mean that nobody here is!
My Point is that this article COULD have meant more if it was brought down to a practical level for home wine makers. Folks who don't have the time or inclination to do all the math to figure out how to apply those findings in practical terms to the home wine maker. This article in a "General Winemaking" has no practical application for the "General Winemaking" folks - Realistically it belongs in the "Yeast, Additives & Wine Making Science" Thread.
Flame on fine, but you are not going to win folks over with vitrol and potshots. People listen to PRACTICAL application of the science in terms they can understand and apply without getting out their Scientific calculators and old Organic chemistry books.
You complemented Mismost who said the same thing and bashed me. So what is it - You don't like the added stories? - Then as you said don't read them. Suggest you use the "Ignore" Option. I certainly will.
Suggestion was for ‘anyone’ to not put a study on blast just because it’s not relevant to you. Wanted to keep from derailment. It did not work.
But “Vitriol ,Potshots, Bashing?” Cmone Really? I disagreed with you. That’s it. Not personal. But sure is now tho. “Ignore button?” B/c why? B/c I think your wrong? I made sure to not be disrespectful too. Read it again when calm*. Seriously.
And I do think saying someone’s post is pointless to you is unnecessary. I’ll stand by that all day. “General” or other. No reason we couldn’t have used that info to discuss possible related practical applications. Like- inches of acceptable headspace in a standard carboy. Or affordable so2 tests for instance.
In your world I cruelly singled you out to bash, and “complimented” mismost. He briefly said his opinion and then his current o2 practices I took what he said and related it to how I approach o2 exposure-and cited the .pdf in the process. Staying on topic. Thinking that’s a compliment clearly shows your on tilt and reacting in a way you normally wouldn’t. Twisting all my words. Immediately Defensive. But It’s ok. I forgive you.
Separate names with a comma.