Paul Gregutt
Wine adviser

Q. I have tried all manner of ways of having one glass of good wine and preventing deterioration of the remaining wine for tomorrow’s one glass of good wine: vacuum, nitrogen, your trick of pouring the remaining wine into a half-bottle, inviting three friends over. Unfortunately, none of these (reliably) works. Now I’ve discovered the single-serving wine bottle. Regrettably, these are not the best wines.  Do any of the better wines come in single-serving bottles, and where might I procure them?
A. Interesting question, which leads me to more questions than answers. Setting aside, for the moment, exactly what might qualify as “better wines,” let’s assume that what will really work best is some method that allows you to open a regular-sized bottle of any wine you like, pour yourself a glass, and save the rest for the next day or two.
It sounds as if you have tried a lot of different methods, and found them lacking. I’m not sure why the Gregutt half-bottle technique doesn’t work. If you are opening a young wine, and if you immediately pour half the full bottle into the half bottle, and immediately push a cork into it, and put it into the fridge, I promise you that will preserve the wine perfectly well for another day or two.
Following along this thread further, you could take the remaining half bottle, pour yourself a glass, and pour the final quarter bottle into one of the single serving bottles you mention. Those are made mostly for the airlines and finished with screwcaps, but that should still preserve your wine for a day at least.
I have never been a believer in the vacuum pumps, and the gas-injection systems are expensive and seem to me to flavor the wine. So I would suggest that you give the Gregutt half-bottle method another try. It really works quite well.

Paul Gregutt, author of “Washington Wines and Wineries: The Essential Guide,” can be reached at wine@paulgregutt.com.