How to store open bottles of wines,

Refrigerating red wine, particularly lighter ones, brings out their fresh fruit flavors.
How full is your fridge? I ask this because you may have to make room for some more bottles. According to a renowned wine expert, any open bottle – even a red – should be kept in the fridge.

Reds in the fridge?

Yup, it’s a thing. Particularly with lighter reds such as Beaujolais and pinot noir. It brings out all their fresh fruit flavors. Even full-bodied reds such as cabernet sauvignon, shiraz and malbec benefit from being served cooler than we’re accustomed to. The advice to “serve at room temperature” dates from the days before central heating. Think cool rather than cold – more like 17C or 18C. If you have space, by all means, pop any leftover bottles in the fridge but bring these fuller-bodied reds back up to cool room temperature before drinking.
Another tip: don’t pour your friends’ glasses too full, especially on a hot day, or the wine will warm up even more.

Singapore weather can be very harsh on wines and the storage of wines here is very poor due to the lack of knowledge.

The rule of the thumb is, the moment you buy a bottle of wine here, chill it in the vegetable section of your fridge for an hour or so. That way the wine will taste better.

What about whites and rosés?

I agree, most are served too cold. Chances are you’ve left the bottle in the fridge all day, which will strip all the flavor out of a white wine, particularly a rich oak-aged white such as burgundy. Even pinot grigio may taste of nothing (which could, of course, be an advantage). Rosés, too, need chilling if they’re not to taste flat and flabby, but a couple of hours should do it.

What about bubbly?

That should be well chilled, otherwise, the cork will fly explosively out of the bottle. Did you know that not only are coupes out of fashion but flutes are too? The best way to serve your champagne – particularly vintage fizz – is in a tulip-shaped white wine glass that tapers towards the rim.

I’ve heard leftover champagne keeps better if you leave a teaspoon in the neck of the bottle?

Champagne is best served in a tulip-shaped wine glass
There’s no scientific basis for it but it does prevent a certain amount of air getting in which will help preserve the bubbles. A purpose-made champagne stopper would be more effective and only costs a few quid. But whoever has champagne leftover anyway?
How long does wine keep once you’ve opened it?
It depends on the wine but most begin to lose their edge after 2-3 days. Even fino and manzanilla sherries (which should be kept in the fridge) are better drunk within the week.
What happens after that? Can you cook with it or should you chuck it away?
If it is still drinkable, yes. If it is corked or tastes like vinegar, no. If you have no call for it immediately, you can freeze it in ice cube trays and use it in cooking as needed.