When it comes to fighting for business travellers, airlines understand that fancy lounges, lie-flat seats and quality service are far from the only weapons in their arsenal.
Meals, and the wines served with them, play a key role in the overall experience which can see a traveller stay loyal or sample the competition.
"Wine still tastes brilliant in the air, it just has to be the right wine" says Qantas wine consultant Tom Carson.
Wine, for instance, is so highly regarded that there's an annual Cellar in the Sky award based on each airline's in-flight selection.
(Qantas has been doing very well in that arena, winning Best First Class Cellar and Best Business Class Cellar plus gongs for the best business class red and first class sparkling).
This week High Flyer sought out the opinions of the wine experts from several leading international airlines on the best drops to drink during your flight.
It's not as easy as choosing your favourite red or white, however, because wine tastes different at altitude.
One reason is the much lower humidity inside the cabin.
"The relative humidity is very dry, which affects your appreciation of the wine's aroma and bouquet because your nasal receptor dries out" says Michael Hill Smith, wine consultant for Singapore Airlines.
Also playing a part is the cabin pressure, which is typically equivalent to around 8,000 feet above sea level. This has a dramatic impact on your tastebuds.
"Certain taste profiles, such as sweetness, are dampened by altitude by as much as a third" explains Robin Padgett, Vice President of Aircraft Catering at Emirates.
"Whilst other parts of your taste palate appear unaffected, particularly in the savoury range, this can subtly change the overall taste profile of a wine."
The key to enjoying wine when you're flying, the experts say, is to choose a drop where those changes work in its favour.
"Wine still tastes brilliant in the air, it just has to be the right wine" stresses winemaker Tom Carson, a member of the panel responsible for choosing Qantas' inflight wines.
"In the aircraft's dry environment you'll find wines with a big fruity flavour and soft tannins are more enjoyable than those with dry tannins or a bitter character" advises Cathay Pacific catering manager Clara Yip.
Michael Hill Smith suggests that travellers should make the most of having such a wide selection of wines literally on tap by sampling half glasses of different wines rather than one full glass of one wine.
"Conduct your own comparative tasting during the flight, but don't drink too much in the dry atmosphere."
"Drink at least one glass of water for every glass of wine" adds Carson.
Many business travellers and frequent flyers love to start their journey with a glass of champagne.
Singapore Airlines is said to buy more champagne than any other airline in the world, and Hill Smith suggests "the overarching principal is that quality will win over altitude and a dry cabin."
"So if the champagne is excellent, it is excellent. Dom Perignon and Krug taste terrific regardless of altitude."
Carson suggests that champagne faces less of a problem than reds of whites "as it's normally served in a narrow glass. For me, champagne is the least affected of all wines that fly."
Even so, the fizz quickly fizzles out.
"Once a bottle of champagne is opened the bubbles are released faster than on the ground, due to the cabin pressure" says Yip.
"If your glass of champagne isn't fizzy, maybe be the bottle hasn't been sealed properly between service."
If that's the case, she suggests asking the flight attendant to open a new bottle.
Ron Georgiou, wine consultant for Malaysia Airlines, points out that temperature also plays a part.
"That first glass of champagne is always too warm, so the wine ends up tasting fatter and broader. By the time you've got that second glass an hour later, it's at the right temperature and a lot colder."
The acid in white wines can be accentuated at altitude, says Carson.
"Very tightly-wound young whites can seem a little tarter and leaner than they do while drinking them on the ground. So on Qantas we fly less young Rieslings and more cool-climate Chardonnays."
MAS' Georgiou also favours rounder, more aromatic wines such as mildly oaked Chardonnay, but says a Sauvignon Blanc demands more careful calibration.
"Quite a lot of Sauvignon Blancs are very green asparagus, very herbaceous" Georgious points out, "and that, I think, translates badly in the air. So Sauvignon Blanc has to be along that passionfruit-gooseberry spectrum rather than that extremely tight green spectrum, for me."
"Red wines with soft easy tannins show well, and conversely red wines with low fruit and hard tannins look even less approachable in the air" says Hill Smith.
"Young dry tannic wines are best avoided" cautions Carson. "Pinot Noir is great. Shiraz and blends of Shiraz with Grenache are wonderful."
"Pinot Noir is fine, as long as you choose something with some ripeness" offers Georgiou.
"Hard Cabernet doesn't work very well, so when you choose your Bordeaux you need to choose something that's been fleshed out with a little bit of Merlot, rather than high in Cabernet", Georgiou suggests.
Another option is a blended GSM (Grenache, Syrah, Mourvèdre) that's big and fruity enough to mask the enhanced tannins in the sky.
I'll admit to a vested interest here, as sticky dessert wines like a Noble One are my favourite in-flight drop.
"Fortifieds are wonderful as a little night cap on a long haul" says Carson. "A nip of Muscat is a brilliant way to end a meal and head off to sleep."
What's your favourite in-flight tipple?
David Flynn is a business travel expert and editor of Australian Business Traveller.