Pretty much uniformly everyone agrees that pouring the leftovers into a container that is precisely sized to accommodate the leftover wine without any air exposure is the ideal method. For example, pouring the leftovers into 375ml stelvin (screw cap) bottle right up to the top and then screwing on the cap.
Others have suggested filling a plastic water bottle with the leftover wine and then squeezing out the air before putting the cap on.
I like both of these methods, but they have a few drawbacks.
First, you may not have sufficient leftover wine to make this method work, at least if you focus on the 375ml method. Second, you may forget which leftovers are in which bottle if you have a few laying around. Finally, I think pouring off the leftover wine does introduce some air into the wine, which might be detrimental in some cases, such as for older vintages.
We visited Tom Anderson at Anderson’s Conn Valley in 2008 and he was an advocate of using argon. I was familiar with people using nitrogen systems (like Private Preserve), but Tom just had a 2 foot high canister (think scuba tank) of argon at his feet that he used to top of the leftover bottles after we had tasted them. I started paying more attention at the wineries I visited and noticed tanks of argon laying around frequently.
Using argon has the advantage of letting you keep the wine in its original bottle and in theory would be effective for almost any amount of leftover wine.
Sparked by this new observation on my part, I picked up a canister of argon at home to try out. I’ve been using it now for about two years. The tanks are big enough that I have only had to replace it once in that time period and the price is very reasonable relative to the small consumer tanks. There is an initial investment in a regulator, but you can amortize this over time if you plan to use the system for long. Replacement tanks of argon run about $40 in my neck of the woods from Air Gas. The regulator set me back about $120 if memory serves.
In order to demonstrate to myself whether or not the argon succeeded, I decided to put together a series of tests. For my initial test, I selected three bottles of the same wine, in this case an inexpensive young wine for practical reasons, and planned to treat each bottle as follows:
Bottle 1 – Decant half the bottle and apply argon to the leftovers and re-cork.
Bottle 2 – Decant half the bottle and simply re-cork.
Bottle 3 – Keep unopened for comparison when we get back to check the results.
I selected three bottles of Cameron Hughes Lot 136, a 2007 Napa Valley Cabernet Sauvignon for my test and made preparations last night for the future test.
I’m still trying to decide how long to wait before for tasting the wines. I think two days at a minimum and three to five days as probably the sweet spot. Seeing as it is Wednesday and I made the preparations last night, I think we will taste the wines on Friday or Saturday, schedule permitting. I plan to have my lovely wife Mona help ensure that I don’t know which bottle is which in the tasting. We will decant half the unopened bottle and set the decanter aside so that the bottles will all be the same weight (no clues permitted!). Hopefully I can recruit another palate or two to corroborate the results.
This test won’t be able to measure the impact of repeated opening and refilling with argon. That’s another, more difficult test entirely.