Characterization of Degassing Equipment and Its Impact on Wine Chemistry

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masic2000

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Conclusion,

This study concludes that the stirring rod can degas a single carboy most rapidly at 13⁰C and down to any desired residual CO2 concentration; however, excessive oxygen may be injected with detrimental effects on wine quality if the wine is degassed excessively. The Gas Getter and vacuum pump used for this study took longer at the test temperature and leveled off at higher levels.

The Gas Getter and vacuum pump dissipated less FSO2 and at a lower rate than the stirring rod. In all cases FSO2 was lost to the environment, i.e. it did not become bound and no longer contributed to TSO2. The stirring rod did however inject O2 at a higher rate than the Gas Getter and vacuum pump.

Full study available here,

http://www.techniquesinhomewinemaki...ent and Its Impact on Wine Chemistry v0.2.pdf
 
This study concludes that the stirring rod can degas a single carboy most rapidly at 13⁰C and down to any desired residual CO2 concentration; however, excessive oxygen may be injected with detrimental effects on wine quality if the wine is degassed excessively. The Gas Getter and vacuum pump used for this study took longer at the test temperature and leveled off at higher levels.

Wow. Obviously, I have not run a comparable test, but this flies in the face of my experience. I formerly degassed with a stirring rod; when I switched to a vacuum pump it was like night and day, with the vacuum pump performing much, much better. Really surprised with this report.

This comment does not affect the overall conclusions, but WTF is going on with the x-axes in this study? They have kinda-sorta random intervals of time, but all marked off in steps of constant distance on the graph. That would be bad, but not awful, but then the graphs have a "straight" regression line drawn through the data points. I think Mr. Pambianachi either needs to study his Excel help sheets or use a real scientific analysis software.
 
Agreed. The x-axis looks weird, numbers are not linear. I thought maybe logarithmic but that's not the case either.

I found this line interesting as well,

"The stirring rod did however inject O2 at a higher rate than the Gas Getter and vacuum pump. To eliminate the loss of free SO2 with the Gas Getter and vacuum pump, sulfite can be added once degassing is completed. This is not recommended for the stirring rod given the higher rate of O2 uptake that may negatively impact the wine without SO2 protection."
 
This testing was conducted at 55.4 F, 20 F lower than my typical degassing temp, and with a much less powerful vacuum pump than the one I use. At the end of the article, he notes that additional tests should be conducted with more powerful vacuum devices. That’ll make all of the difference, I suspect. It took 18 minutes to get down to 500 with the paddles, my pump produces undetectable CO2 levels in 75F wine in under 5 minutes.
 
One guy running some one off tests with results that are so vague that he says,

"Test Errors. Accuracy and precision of tests was limited by
available instrumentation and analytical methods. Test results
are provided without accuracy/precision analysis."

doesn't rise to the level of 'study' in my book. More like an exercise. He sounds like some guy that has a little more than the average wine maker equipment wise. I read it but there wasn't enough there to give me any confidence that his results really had any validity for wider application.
 
One guy running some one off tests with results that are so vague that he says,

"Test Errors. Accuracy and precision of tests was limited by
available instrumentation and analytical methods. Test results
are provided without accuracy/precision analysis."

doesn't rise to the level of 'study' in my book. More like an exercise. He sounds like some guy that has a little more than the average wine maker equipment wise. I read it but there wasn't enough there to give me any confidence that his results really had any validity for wider application.

I think he is a little more than just your average winemaker equipment wise.

"Daniel Pambianchi is an avid and seasoned winemaker both as an amateur and professional having owned and operated for 10 years a small commercial winery in Niagara (Ontario, Canada). He is the author of several bestselling winemaking books, including Techniques in Home Winemaking. Daniel has served as past Technical Editor and author for WineMaker Magazine. He has lectured at conferences on a range of subjects from wine analysis and chemistry to advanced winemaking techniques. Daniel now provides consulting and analytical lab services to both amateurs and professionals." I believe this was a very quick look at a few different ways to degas and what effect they have. One of his big things in winemaking talks is that homewinemakers don't pay enough attention to dissolved Oxygen and it's effects on wine.
 
@1d10t Daniel Pambianchi isn't just some guy in the winemaking world, he's well accomplished and published, and apparently the "corresponding author" on this article. Despite that, I do a agree with your evaluation, there are so many stones left unturned here, and the conclusions reached in this "study" fly firmly in the face of all of my personal experiences with degassing wine. Personally, I give the article no credibility unless one intends to degas wine at 55F with an underpowered vacuum pump.
 
My $0.02

First off as others have said Dan is highly respected in the winemaking field/industry. Not sure why 55F was chosen for a degassing experiment which is what this was. Everyone knows (or should know) CO2 comes out of solution faster and easier at higher temps so if your trying to optimize getting rid of something as quickly as possible why would you choose a temp that holds in what your trying to get rid of? Maybe I missed the part that explained that. This experiment is now 6 years old. Wonder if any of it has been reanalyzed with current techniques and technology?
 
Obviously my observations were made solely based on the article. It is 5 years old I believe. I had no preconceptions of who the guy was so I called it as he came across in this 'study' as far as I'm concerned. The way it was presented I'd personally give it no more weight than some of the forum members here. I've degassed one wine with my 45? year old refrigeration vacuum pump and had much better results than he got.

Coming from a home brew background I think I've mentioned before good science is much harder to track down with wine making. Beer is an industrial product that is well studied and researched by the big companies out there. So far I'm not finding the same level quality of hard information as I can with beer. It may be there but I'm not finding it yet.
 
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Just for reference when I used an online calculator 600 mmHg is 23.62 Hg which is ~ what the AIO pulls. The qualification is as follows although I don't know excatly why it's used: 600 millimeter mercury (0 C) = 23.622137 inch mercury (32 F).
In a quick briefing I'm not sure why he provided this study and surprised he would publish an article that he himself admits is inconclusive. I do see his point that the stirring rod he speaks of agitates the entire carboy moreso then the vaccuum and could potentially increase the release of CO2 at a higher rate. I've been finding a few articles on Dissolved Oxygen and have to agree with @cmason1957 on this issue. I haven't yet gotten to understand what the ill effects of DO are but it appears to be a real thing. Infact Daniel has a little blurb on the Vinmetrica site praising them for coming up with the DO analyzer. Out of context a little but this year my Christmas wishes are a DO Analyzer and and inert gas set up. From what I think I understand running an inert gas through the wine removes DO and the magic number is under 10 ppm.
 
@mainshipfred--If you wanted to start an inert gas thread separately, that would be cool. You'll have at least one person to comment (me) as I am thinking of doing the same thing. I used a Co2 set up when I was brewing, and given the cost and efficiency aspects, I am thinking of going back to the same, understanding that a trace of CO2 may re-dissolve in the wine. I also have an Argon/CO2 (75/25%) set up with my welder, but the bang for buck is with CO2 which has 4 times the amount of gas in the same size cylinder due to the phase change from liquid to gas. And a fill is far cheaper too.

I think we could also use a thread on sanitary fittings (tri-clamp or tri-clover-same thing) and how they will all work well with vacuum transfers or pressure transfers.

I do think the whole degassing thing is overblown (sorry, could not resist!) Time, a couple of vacuum rackings and it's a non-issue. I bottled my 2017 at 10 months, and it was sufficiently degassed. Going to do the same with the 2018.
 
Do you want to start the thread since you appear to know way more about gases then I do. I have read the warnings of using CO2 in wine and I thought the reason was possible carbonation, maybe you're saying the same thing. I don't know about the 75/25 set up, is that 2 different tanks regulated for the percentages or is it a pre mixture? I know the wineries I'm familiar with use Argon since it's cheaper then Nitrogen which is the other inert gas commonly used. The other thing about using gas is I don't know how much is actually required for a home winemakers operation. It could be the price difference may not play a huge role. From what I can tell gas is relatively inexpensive compared to the set up.

As far as tri-clamps you must make much larger volumes then I do. My largest tubing is a 1/2" ID and it just slip over my canes or perhaps you are referring to something different.
 
Do you want to start the thread since you appear to know way more about gases then I do. I have read the warnings of using CO2 in wine and I thought the reason was possible carbonation, maybe you're saying the same thing. I don't know about the 75/25 set up, is that 2 different tanks regulated for the percentages or is it a pre mixture? I know the wineries I'm familiar with use Argon since it's cheaper then Nitrogen which is the other inert gas commonly used. The other thing about using gas is I don't know how much is actually required for a home winemakers operation. It could be the price difference may not play a huge role. From what I can tell gas is relatively inexpensive compared to the set up.

As far as tri-clamps you must make much larger volumes then I do. My largest tubing is a 1/2" ID and it just slip over my canes or perhaps you are referring to something different.


Thread started under Equipment and Sanitation

Regarding tri-clamps sanitary fittings, you're right, not 100% needed but makes for a a clean and flexible system that's easy to sanitize. There are fittings to use 3/8 and 1/2 in tubing and everything else as you can imagine. Plus fun to use in the same way that Legos were fun to play with when we were kids.
 
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