The Full Bottle: How to keep wine fresh to the last drop

Q: Is there any way to keep an open bottle of wine fresh for the next day? M. McKenzie, Canterbury, Vic

Yes. Just put the screw-cap back on and stick it in the fridge. Most wines will be as good the next day. Why the fridge? Because the chemical reactions that cause wine to go stale or oxidise happen more slowly the colder the wine.

Some wines resist going stale from air contact better than others. Young riesling is one of the best. I'm currently tasting a lot of 2017 and '18 vintage rieslings – Australian, New Zealand, German, Alsatian – and they all taste just as good the next day, even if they've not been refrigerated. Why is this? Probably because they have low pHs and high acidities, and the protective power of the preservative sulphur dioxide is much more effective in low-pH wines. Opened bottles will keep for several days in the fridge with the cork or screw-cap firmly replaced.

Screw-capped wines tend to keep better than those under cork. After doing a large tasting, I often top up the best wines with something similar – say, one chardonnay with another chardonnay of comparable quality – and replace the screw-cap. I'm amazed how long these wines can last. Several months, even a year – no problem.

On the other hand, red wines tend to show staleness sooner. Aged reds especially tend to smell and taste a bit stale the next day. Whether they're acceptable depends on your palate.