How do brewers make zero-alcohol beer?

−A.H., BEECROFT, NSW

Beer is pretty simple stuff – just water, grain, hops and yeast. The yeast ferments the sugars in the wort – a slurry made by mashing the grain – which produces the alcohol. Water is the main component.

One way of making low-alcohol beer is to simply water it down, diluting the alcohol – and everything else, including, alas, the flavour. Not ideal if you want beer with character.

The most common way to remove the alcohol and produce low- or no-alcohol beer is to distil normal-strength beer under a vacuum. The boiling-point is much lower under a vacuum, so the alcohol boils off without spoiling the flavour. Normal hot distillation would cook the beer.

Other methods of de-alcoholising normal beer are reverse osmosis (a kind of filtration) and spinning cone distillation (which works like a centrifuge). Reverse osmosis is expensive and probably only practical for the big breweries.

It seems to me that brewers are having much more success producing no-alcohol beer than winemakers are producing no-alcohol wine.

Before no- and low-alcohol beers became fashionable, there were some “beers” that were made entirely without fermentation. These just simulated the taste of normal beer using added flavourings and enzymes, with very limited success. You can’t really call the result beer.

It seems to me that brewers are having much more success producing no-alcohol beer than winemakers are producing no-alcohol wine. I’ve enjoyed Heaps Normal and Dainton’s New Age XPA lately; they taste pretty close to the real thing.

Like all non-alcoholic beers, their containers are stamped with the words “Less than 0.5% alc/vol”. Legally, a beer (or wine) can be called non-alcoholic if it contains less than 0.5 per cent alcohol. That’s because when a brewer starts with a normal-strength beer, no method of de-alcoholisation can remove all of the alcohol. Which is something to be aware of if you have a serious allergy to it.