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Why do low and non-alcoholic beers taste so much closer to the “real thing” than non-alcoholic wines do? (continued)
Andrew Tyrtania
Lidlington, Bedfordshire, UK
There are two main types of beer: ales and lagers. Until very recently, I would have said no one has produced a drinkable non-alcoholic ale, but that has changed. Low-alcohol beer, also called small beer or table beer, has been produced for centuries, simply by starting with less sugar from less grain, or “second runnings”. This is when you rinse, or “sparge”, the grains a second time, producing two beers from one load of grain.
There are broadly two ways of making a non-alcoholic beverage: manufacture it with no alcohol, or make it as before and then extract the alcohol. The former has been practised for a long time with wines – it is called pasteurised grape juice. But even the latter has been done since the 1980s, using a process known as the spinning cone column. This relies on gravity, centripetal force, heat and a slight vacuum to separate the various components, which can then be left out (i.e. the alcohol) or recombined into the final product. The simple way to remove the alcohol is to just boil the wine or beer, but this has deleterious effects on flavour for both. Using the vacuum reduces these, as boiling takes place at lower temperatures under reduced pressure.
Turning to beer production, the choice and combination of grains and the temperatures used to make the wort (the liquid foundation of beer) can make a big difference to the end product. The brewer can determine which sugars are extracted, including reducing the maltose, from which most alcohol is produced. Hop additions are also at the brewer’s disposal, and these, too, have a big impact on the beer.
Consumer interest has led to massive recent innovation. Brewers now have not only pure hop oil extracts to add into their final beer, but also specialist yeasts, engineered to produce little or no alcohol while still producing the other desirable flavour compounds that contribute to the final product. Yeasts, like fruit flies, reproduce rapidly, so they lend themselves to genetic engineering. Breeding has been employed to produce new, exciting yeast strains, as has CRISPR technology.
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Yeasts reproduce rapidly, and breeding has been employed to produce new, exciting yeast strains, as has CRISPR technology
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During the same period, we have also become used to craft ales, which generally offer a fruity, hop-forward flavour profile and less malty character. Producing low- or no-alcohol beers of this character is more likely to succeed.
Mouthfeel, or body, is mostly determined by components other than alcohol, but we can still detect when it isn’t there. With beers, you are typically removing 3.5 to 6.5 per cent alcohol by volume, while for wines, this may be 11 to 14 per cent – a much more noticeable change in composition.
Craft beers and all non-alcoholic beers have to be artificially carbonated, as yeast produces most of the CO2 at the same time it is producing alcohol. Any sort of treatment to reduce alcohol, such as vacuum distillation, filtering, reverse osmosis or arrested fermentation, will remove CO2 from the beer. As such, you are unlikely to find non-alcoholic beer on hand pump from cask any time soon (ditto for non-alcoholic champagne). But I would say watch this space – it can only be a matter of a few years before very drinkable non-alcoholic wines appear on the shelves. All eyes are on the yeast suppliers.
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