Over the past year, since receiving a Caravin as a gift, I’ve opened maybe 30-40 bottles after sampling with the Coravin, usually within a few days, sometimes immediately after (I.e. I start with a taste, like it, then say, "screw it, I’m just going to open the whole bottle). Rarely has the bottle sit for more than 2 weeks.
I have noticed often significant differences between the Coravin pours, which often seem cleaner, fresher and more developed, and the subsequent open bottle pours, which are often tighter and less aromatic. I have also had the experience of a bottle with a fairly clean Coravin pour that was heavily TCA inflected when opened.
I will note that I am mostly sampling young (<10yo) wines, and am rarely decanting after I open.
Wondering if others have had similar experiences and how they explain it…
I think volatile aromas escape into the headspace of bottles tapped with the device. Wines never really show oxidized but they’re often muted and boring.
Are you pushing argon through the needle before inserting it into the bottle? If not, you’ll be adding a bit of air each time you use it, which will have an impact (exactly what depends on the bottle).
I’ve only noticed muted wines after several weeks. I think the device is wonderful for keeping a wine for a week or two, beyond that I’m not convinced.
We had a bottle of “by the glass cab” we poured from for four days using the Coravin. Thinking that was enough, we pulled the cork and polished off what little remained. It was excellent. Might have got just enough air to bring it around by day four.
Have kept wines for mo this to good effect and no deterioration, though I refrain from using it on old or questionable corks with the standard needle.
Eric: I usually prime but sometimes forget. Haven’t noticed a big difference.
Not sure if the wines are muted when opened. Would say that, if anything, the coravin pours seem more vivacious and better aerated and less tight. BUT, opened bottles post Coravin seem to be about the same opened bottles that were never Coravined. So I don’t know that Coravin somehow made them worse, just That the Coravin pours were better…
I’m a winemaker. I use the Coravin for taking my wines out on sales calls, so I’ve used it on numerous occasions with the same wines. Week and a half to two weeks, and the wines change, not as fresh. If anything I could relate it to, I’d say it reminds me of shock. I use Diam corks and question how quickly they reseal. I’ve started turning the bottle upside down or on the side with the thinking that the wine would help clog the opening.
I use a Coravin on a semi regular basis, if I start on a Monday, depending on the wine, it generally shows fairly close on Friday. The closure makes all the difference, lots of leakers using diam and other than cork closures. For some of my customers it gives them a bit of confidence that the wine will be somewhat sound vs. a opened bottle with a cork sticking out wondering how I manipulated the wine to taste good (lots of tricks)
It works better in larger framed Cabernet based wines, and less so for Pinot, saying that, I’ve had better luck with Sonoma Coast Pinot than Willamette Valley Pinot.
Would I buy one now that I have used it for home consumption? Maybe.
First coravin oxidized bottle
Coravin’d a 1998 Château La Gomerie- France, Bordeaux, Libournais, St. Émilion on 2/27/2016 (It was superurb, 94+ maybe even 95, a legitimate candidate for wine of the year), and again on 3/4 (a week later, consistent great outcome). In between it was stored in a dark corner of the cellar, standing. Today, there was slightly less than half left, so the decision was made to just open it and finish it. Opened, poured to the glass, and… taste like Japanese soup base. Oxidized, bitter, just… well, all ‘off’ wine. Not even close to the nose I had before on the wine, the taste or the finish.
I was sad, and confused. I used coravin on younger wines for the same period or even longer with no problem, but this one was truly a “wine killer”. It is the second oldest wine I’ve coravin’d (I did coravin a '94 from Sonoma before and tested it over 10-14 days with no problem). But, it made me concern. Maybe I can’t extend the joy of truly old wines with the coravin that much. Or maybe I used it incorrectly? either way, I now have a heart pain watching a great La Gomerie that maybe be good for cooking.
My two cents,
In the past, I have had a lot of variability with wines that have been tapped multiple times. I initially thought it might be caused by forgetting to prime the needle prior to tapping. Later, I noticed that I was getting a pressure differential (hissing) on many of the second and later taps. I also happen to store my tapped wines in the coldest part of my cooler.
My conclusion is that the headspace in the bottle equalizes at the temperature that the wine is initially tapped at. If the wine is subsequently colder when it is tapped the second time, a vacuum will be created in the headspace and air will be sucked into the bottle. Subsequently if the bottle is warmer than the initial tap temperature air will escape from inside the bottle and not create an issue. This issue is easily remedied by making sure the bottle is not colder than the first time it was tapped. I’ve discussed this with Coravin customer service suggesting they inform customers of the possibility and also suggested adding a valve to future models for prevention. They were firm in their reply that this is not an issue and that it is likely air escaping from the bottle. Which I’d agree with if the bottle had never been tapped. Coravin customer service has been very responsive and helpful with other issues.
I spent a considerable amount of time talking with Oenologists, winemakers and gas scientists a while back when I was working on an Argon injection device for wine preservation. I’m not an expert on the science here but I do understand the mechanics of some of this. You’re saying that the gas mixture (Argon +air) in the headspace will contract when cold, and I get the possibility of that although this never came up in all the discussions I had about how to know how much Argon to pump into a bottle before re-corking it, or temperature of storage - (ie.- allowing for that or requiring later Argon injection). What I wonder, in regard to a Coravin, is why doesn’t air enter continuously through the needle hole, or around the cork if a vacuum is created when the wine is cold enough, and how this would happen only when Coravin’s needle is inserted a second time. I’ve seen enough comment questioning the completeness of the re-sealing on corks or different types to not be surprised in air can get in or out.
I’m particularly curious because my research also recommended that all wine be refrigerated after opening if it was going to be kept more than a day or so to slow down any degradation. I would have thought that the idea of contraction sucking in air would have come into that discussion, but maybe it didn’t because the method I was using had the whole cork (no needle hole) returned to the bottle to seal it.
My premise is that when you tap the wine the pressure will equalize based on the temperature of the wine at that time. The coravin has a two-way valve, it either provides access to the argon capsule and is closed to the outside environment or it provides access to the outside environment. When the bottle is tapped for the first time it is not uncommon to here a small hiss. I assume the bottle is commonly under pressure due to the cork being inserted into the bottle (the cork seals the bottle and then the headspace is compressed). When the bottle is first tapped, the headspace pressure quickly equalizes with the ambient home pressure because the needle provides a path for gas exchange. When the trigger is pushed the valve closes access to the home ambient environment and allows the argon capsule to pressurize the bottle. Release the trigger and wine will flow as long as the bottle is tilted appropriately. If the bottled is placed upright before the wine stops flowing, excess argon will be released from the bottle and the pressure in the bottle will be the same as outside the bottle. At this point you could theoretically leave the needle in the bottle and air will not enter the bottle as long as the environment is warmer then the wine temperature. When you remove the needle the headspace pressure will be at equilibrium to the environmental pressure at the specific temperature of the wine in the bottle, say 65F. The cork is theoretically sealed at this time and the wine is placed back in the cellar and cooled to 55F. If the ambient environmental pressure is the same there will be a slight vacuum created in the bottle when the temperature decreases. Changes in barometric pressure will also affect the headspace pressure. I have not performed calculations to determine what pressure differentials can be created and if they are significant. I concluded that air was entering the bottle because I had several instances of wine changing significantly from the first time or two it had been accessed and the fact that a hissing sound was sometimes observed a second or third time the wine was accessed. This is just a theory as I have no proof if air is being sucked in or if it is being pushed out. There is definitely a + or - pressure differential when the hissing sound is heard. Anecdotally, I’ve had more consistent results accessing wines since I have become aware of the potential issue.
I’m sure a lot of people will argue that Argon is heavier than air and it will cover and protect the wine. That has not been my experience. Argon will help but all gasses are constantly in motion so oxygen can still come into contact with the wine.
I’ve never seen a Coravin work in person so I can’t really comment on the mechanics of the unit. When I inject Argon into an open bottle (no matter how much I inject) and seal it with it’s original closure, I always refrigerate it. I’ve never noticed a hissing suggesting a release of gas when I open the bottle. Not sure why that would be different.
What I’ve found a bit difficult in these discussions is just how specific people are about the negative impact of a tiny bit of oxygen in the small amount of air that might get into the bottle, especially when we’re only talking days in many cases. I guess that’s about palate sensitivity and wine stability, but it always intrigues me.
As to your last paragraph, everything I was told in my research said that gases MIX and don’t stay separate, so oxygen can contact the wine but only in proportion to the total of it in the mixture of Argon plus air in the empty space. The example one scientist used was to suggest that if Argon were truly ‘heavier’ enough than air we’d be walking around with Argon at our feet (or whichever gas were the heaviest, but there’d be layers - which there aren’t). I still, however, note people who talk about the ‘blanket’ of gas that protects the wine after injection of it into the bottle (regardless of the device).
Your last paragraph is exactly right, the gases in the head space are essentially completely mixed, so that any oxygen that makes it in will find its way to the wine.
For the case you mentioned (65F dropping to 55F), the pressure would drop by approximately 2%. Whether that’s enough to suck air in through the small hole, is difficult to say but I would have thought it didn’t. The fact you hear the hiss when tapping it a second time (if immediately after brought from the cellar) would suggest the hole didn’t leak enough for the pressure differential to be neutralized. Does the hiss sound different or similar depending on the number of days between the first and second use of the Coravin?
The hiss is variable… sometimes none and sometimes a lot (~1 second). The only theory I could come up with is the barometric pressure differences (not much effect) and temperature differentials. I’ve had tastings with two to four people and a dozen wines. The wines are accessed and stay on the counter. It is likely they reached ambient temperature, but still you’re only talking another 10F. I haven’t had the hissing issue since becoming aware of possible causes and mitigating them. I no longer store accessed wine for long periods of time, especially if it has been access more than once.
You’re right that the barometric changes are less important. Once you have taken out a few ounces of wine, the temperature change of the wine is less important than of the gas in the headspace. It’s really the temperature of the argon you put in (presumably room temperature) vs your cellar temperature. The reason is that the wine doesn’t expand or contract very much. In a full bottle, the small volume change in the wine can be significant compared to the volume of the headspace. Once the headspace is larger, the volume change of the wine is much less important.
I wouldn’t suspect a slight pressure differential would be noticeable when pulling a cork. The Coravin has a small needle which restricts the airflow thereby increasing the time it takes to equalize. I’m not talking a big pressure differential, I’d say the worst ones are ~1 second long or maybe half that long.
All the wines I mention had a remarkable difference in taste. They are wines that have been accessed for months up to a year+. I agree that it’s unlikely for someone to notice a difference within days. I don’t know what caused the difference in taste I observed. It’s been mentioned that volatiles enter the headspace, etc… I have had some older cab. magnums that have tasted more oxidized each time they were accessed so I definitely contribute that to oxygen.
