In Japan, mixologists freeze water into large blocks before hand-carving them into spheres, diamonds and other abstract shapes. In LA, luxury ice supplier Névé Ice provides upscale bars with 48-hour deep-frozen custom ice; reputedly using water taken directly from glaciers and able to withstand being dropped onto concrete without smashing.

For barflies who travel frequently, ice is the next big thing. Yet here in Hong Kong, bartenders are left to their own devices to ensure the ice they serve - and we imbibe - is of the highest standard. So how do they do it?

There are four basic types of ice: block, cube, cracked, and shaved, and each have their own uses. According to Kelvin Kwok of Blue Bar, "large blocks and spheres are used for straight spirits on the rocks, while cracked ice melts faster and adds more water to drinks and is usually found in frozen drinks." Crushed ice is found in drinks best enjoyed diluted, such as the Mint Julep.

Mixologist Max Traverse at Le Boudoir adds, "shaved ice should be used when spirits form the principal ingredient of the drink - and no water is employed. When egg whites, vermouth or other mineral waters are used, it is better to use small lumps of ice." Not only used for cooling drinks, ice can be used to release flavours in spirits such as whiskey. "Taste and temperature are the two key factors for cocktails and ice is that one element which directly affects these two factors," says Calvin Ku, F&B Director at Lily.

So why is ice important? Any bartender will tell you the hidden secret to a successful cocktail lies in the quality of the water that goes into it. Ice made with hard water with high mineral content can have a distinctive taste, whereas soft water usually has a slightly salty taste with a tendency to leave a soapy residue, making it unsuitable for ice. It also melts quicker, affecting the taste of the drink in the end. Hong Kong's tap water is quite hard, and a solution used by most sophisticated bartenders is to use double or triple filtration devices which neutralize the mineral content, removing as much 'taste' as possible to avoid flavour fluctuations.

Nobu and Spoon at the InterContinental only use purified or distilled water for ice making so as not to affect the taste of the drinks. Lily only uses ice suppliers who can provide ice made purely from spring water, maintaining their stringent levels of quality require the ice to be completely odorless and tasteless.

In all but the most exclusive of bars and hotels, drinks are routinely made with bagged ice, typically cracked. The ice is the standard, cylinder-shaped ice, often hollowed out, which form the basis for practically every drink made in our city. The cylinders are quick-melting and specifically designed to cram as many of them into a cocktail glass.

In Traverse's opinion, "this sort of ice cheats the customer, the ice really is terrible for cocktail-making". At Le Boudoir, the ice used is of the solid block cube, made in-house. Traverse continues: "as bartenders, it's a matter of cooling things down, and our only ingredient to help us do that is the ice we use. Using cheap ice is a horrible way to make a beautiful cocktail turn bad."

Lily uses a large block of ice, which is then hand-carved with miniature ice picks and saws into cubes, diamonds and shards for drinks with a purist approach such as their 23-year aged rum Old Fashion or a straight-aged scotch.

Nobu uses copper moulds to shape large, over-sized ice spheres, made with distilled water and frozen for over 12 hours. Size, density and volume all count as ice with air bubbles or cracks melt much quicker. Shiny ice is also a bad sign as it will melt faster and accelerate dilution. It's also incredibly important to use only the freshest ice possible, as ice absorbs odors very quickly.

But what of the budding mixologist looking to entertain guests at home or beyond the reach of a professionally-run bar? Ice moulds and ice-making machines are respective steps up the ladder to custom-designed ice, but Traverse warns that while a simple spherical ice mould like those found in Muji stores offers stay-at-home drinkers the chance to experiment with spherical ice, "the ice will definitely have cracks in it, meaning it will only hold its temperature for a short while, diluting the mixture quickly and not retaining temperature." Ice-making machines regularly cost upwards of HK$25,000 and have yet to have the Philippe Starck treatment, leaving you with a potentially large and rather ungainly kitchen appliance.

So when will we start seeing gourmet ice suppliers similar to Névé cropping up in Hong Kong, as the influence of New York's night-life trends continue on our shores? The importance of ice cannot be underestimated, but as Ku quite rightly concludes: "ingredients are still the most important aspect of a drink. I can make a decent cocktail with poor quality ice, but I will not drink a cocktail made with bad spirits." There are, as yet, no adverts on the sides of trams advertising Hong Kong's very own ice-from-a-Himalayan-glacier but take our word for it, it's only a matter of time.

The full version of this article first appeared in Revolution's issue 14.