Ovaltine's distinctive orange-coloured jars can also be found in all of Hong Kong's major supermarkets and other retail stores, and tens of thousands of local kitchen cupboards.

But how did this distinctly European product become such an integral part of life in the subtropics?

The first consignments of Ovaltine to arrive in East Asia were exported by Britain to her colonies in the early 1920s. Ovaltine's golden years in Britain were the 1930s, '40s and '50s. But since the days of empire, the drink has enjoyed enduring popularity here.

And, according to hot drinks sector industry insiders, the 1997 handover had no effect on local sales or consumption.

Although the Ovaltine now available in Hong Kong shops is manufactured in Thailand, the brand would seem to be more British than cornflakes (actually American), Heinz baked beans (also American) or chicken tikka masala (first concocted near London).

But the Ovaltine story began more than a century ago in Switzerland. When chemist Georg Wander, toiling in his Berne laboratory, devised a cheap, efficient process to produce malt extract, he realised that the viscous syrup could form the basis of a highly nutritious drink.

The philanthropic Wander then set about creating a product to fight malnutrition, and started adding additional vitamins to his elixir. There was one problem, though: it was not palatable. However, Wander's son, Albert, was sufficiently excited by the project to develop it further. In 1904, Albert created 'Ovomaltine' by adding sugar, whey and beet extract to his father's creation, thereby improving its taste. Then he marketed it as an energy drink - the Red Bull of its day, as it were.

It caught on quickly in Switzerland, especially with skiers who found the piping hot health drink fortified them against the cold. In a short time, word of this remarkable product had spread beyond Switzerland's mountainous borders.

Britain was an early convert and embraced Ovomaltine in 1909, renaming it Ovaltine. The now universal chocolate version came along a few years later.

The brand received two massive promotional boosts in five years. Ovaltine was designated the official drink of the 1948 London Olympics, and was widely reported to have been carried up Mount Everest by Sir Edmund Hillary in 1953.

In recent decades, Ovaltine's popularity has waned in the west, due to the perception of the drink being primarily a nightcap for the elderly war generation.

In Asia, however, it has been a different story. Ovaltine's popularity has endured and remains strong. According to retail-industry sources, Hong Kong, Thailand and the Philippines are three of its biggest markets and are leading in global per capita consumption.

So, why does this originally North European Alpine beverage perform so well in Asia?

Its popularity in this part of the world is in part due to it being acknowledged as a long-running and highly respected brand. But perhaps more importantly, it enjoys a well-deserved reputation as a tremendously healthy product.

Ovaltine mixed with milk provides a solid helping of vitamins A, C, D, B1, B2, and B6, as well as niacin.

Research suggests that it is beneficial for expectant mothers and young children. Mami Lam, a Discovery Bay mother of two, said: 'I add it to milk to make a more flavoursome and nutritional drink. My three-year-old son, Luke, wrinkled his little nose at it at first. But now he gulps it down, especially in the winter months.'

Napoleon Wong is a fairly typical adult Ovaltine drinker. An IT consultant, he is in the habit of taking his mid-afternoon 'screen-breaks' in a Sai Wan Ho eatery, often with a mug of Ovaltine at hand, steaming hot in winter and iced in summer. 'I used to enjoy Ovaltine as a child in the morning. But now as an adult I find it acts as an afternoon pick-me-up when I want a change from yuen yeung' [coffee and tea, mixed together, Hong Kong cafe-style].

Twelve-year-old Thomas Hua Kang of To Kwa Wan said: 'We always have a jar of Ovaltine in the kitchen. It tastes great and gives me energy for football.'

Hong Kong's hot drinks sector is fiercely competitive, with market data being subjected to the utmost secrecy.

It is generally accepted however, that Ovaltine, Horlicks and another Swiss player, Nestle's Milo, dominate the market.

Annie Sin, marketing communications manager of Wellcome supermarkets, said: 'All the brands are continuing to sell well within seasonal expectations. Come the cooler months, we'll be selling even more.

'Mothers and students appear to form the bulk of our hot drinks customers.' From its Swiss origins, Ovaltine is drunk in markets as far afield as Brazil (where it is often enjoyed mixed with vanilla ice cream) and Nigeria.

Consumption patterns point to some cultural differences.

Ovaltine has long been viewed in the west as a bedtime drink.

But in Hong Kong, it is most often served by mothers to their young children to set them up for a day at school.

For the Thais, any time is a good time for the healthy brew and it is even available on draft in convenience stores.

Some things, however, do not change. Ovomaltine, as it is still called in Switzerland and where it remains hugely popular, retains its healthy association with skiing.

And doubtless the sight of 21st century winter sports enthusiasts quaffing steaming mugs of this iconic beverage would make the Wander family proud.

But who can fail to wonder what the Wanders would make of their product's world-beating success today, especially in light of the planet's most avid Ovaltine drinkers, who are partial at this time of year to iced Ovaltine in the air-conditioned teashops of Hong Kong and Bangkok.