The Science of Non-Alcoholic Beer

By Brent Rose on at

"Blasphemy! A crime against nature!" Yes, many people feel the same way about non-alcoholic beer as they do about decaffeinated espresso. "It's just wrong and what's the point?" is the thinking. Yes, yes, you're very cool, now sit down and shut up.

While it may not be your drink of choice there are plenty of very valid reasons for drinking non-alcoholic beer. Maybe you're pregnant and miss the taste. Maybe you're a designated driver, or you're on antibiotics. Maybe you just don't feel like getting intoxicated, but you'd rather look like you're drinking the same thing as your co-workers and social dynamics are weird. We're not here to judge. We're here to check out this interesting animal.

How're they made? Why are they almost always terrible? Why isn't there a non-alcoholic IPA? Let's find out.

 

A (Very) Brief History

Non-alcoholic beer first started popping up in the U.S. in 1919. Why? Prohibition. It was decided that the strongest a beverage could be is 0.5 per cent alcohol by volume (ABV). If that number sounds familiar, it's because that percentage has stuck, and "non-alcoholic" beers today still have 0.5 per cent ABV as their upper limit. So, some of the large breweries began making "near beer," stuff that was very pale, didn't have much flavour, and was right at 0.5 per cent ABV.

13 years later, and Prohibition was banished like the abomination it was, but something happened in that time. A lot of people had developed a taste for that super light, bland (compared to the ales of the day) beer—a sort of alcoholic Stockholm Syndrome. For the breweries that had been making the "near beer" during Prohibition, it was pretty easy for them to carry on as usual, but they left more of the alcohol in. This is a partial explanation for the popularity of the light, bland lagers (Miller, Coors, Pabst, Bud, etc.) in the U.S. though, it should be noted, that even science cannot fully explain it.

 

How Non-Alcoholic Beer Is Made

Non-alcoholic beer (or NA beer, as it's sometimes called) starts its life as a normal beer. In fact it goes through almost the full process, from making a mash, boiling the wort, adding hops, and even fermenting. Here's the fork in the road, though. While regular beer will then be bottled (or canned or kegged) and aged, non-alcoholic beer has to have its alcohol removed.

The most common way that alcohol is removed from beer is through heating. As we've discussed in several previous articles, alcohol has a much lower boiling point than water. At sea level, it's roughly 78 degrees C. The fermented beer is heated up to that point and kept there until the solution is only 0.5 per cent ABV. However, heating changes the flavour of the beer significantly, because you're cooking all of the ingredients again. To minimise this, some operations practice vacuum distilling. Depending on the power of the vacuum, the alcohol's boiling point may be lowered as far as 50 degrees, which is much less disruptive to the flavours. (With a much more powerful vacuum the alcohol could be made to simply evaporate at temperatures lower than 10 degrees C, however these sorts of vacuums are not used for large scale vacuum distilling.)

Another technique that's sometimes employed is reverse-osmosis. As Chow.com explains it, "...beer is passed through a filter with pores so small that only alcohol and water (and a few volatile acids) can pass through. The alcohol is distilled out of the alcohol-water mix using conventional distillation methods, and the water and remaining acids are added back into the syrupy mixture of sugars and flavour compounds left on the other side of the filter. Bingo—a nonalcoholic (or dealcoholised, as winemakers call it) brew." Because the main ingredients aren't heated, this technique causes less flavour degradation, so it gives generally preferable results, though it's more labour intensive and requires more equipment.

Even after the alcohol is removed, we're not done yet. We've got some liquid that tastes reasonably like beer, but it's flat. Most respectable beer carbonates itself as it finishes out the fermentation process inside its bottle. As yeast is metabolising sugar into alcohol, one of the byproducts is CO2, which gives you bubbles. However, our now non-alcoholic brew has no more yeast and it isn't fermenting. Most producers of non-alcoholic beer simply inject the brew with CO2 during the bottling (or kegging or canning) process. So it's really sort of a beer-flavoured soda. Others will toss in a little bit of starter yeast with a little more sugar and let it ferment in the bottles, but this is a trickier process, since you are liable to reintroduce a small amount of alcohol. Also, you're bottles may explode if you do it wrong.

Note: Some regular beers employ these techniques for carbonation as well.

 

Why It Tastes Different

Drinkers will probably tell you, "Because it doesn't have alcohol! Duhhh!" then walk away picking their noses and feeling smug. They're not entirely wrong, but more than flavour, alcohol adds to the mouth-feel of the beer. It gives it that dryness, and it can accentuate some of the sweet flavours in the malt, but alcohol doesn't really add any flavour itself.

The largest culprit is the alcohol removal process, especially when heat is involved. Generally speaking, hops are added at three stages of the boiling process: the early hops are to add bitterness, the later hops are for flavour (piney, citrousy flavors), and then they're added at the very end for aroma. Some beers (especially IPAs) are also dry-hopped, meaning hops are added to it for a period of time after the beer is removed from heat. The bitterness of hops is pretty hearty, as is the beer's malty sweetness. However, the flavour and the aroma are far more delicate, and aren't likely to survive the reheating for alcohol removal.

According to Brew Your Own, "The hop aromas will usually be driven off within the first five minutes, while the hop flavours will be gone within the first 15 minutes." This is why neither we nor any of our sources have encountered a half-decent non-alcoholic IPA, which is a damn shame, really.

Another common complaint you'll hear about NA beer is that it has a metallic or sour taste. This problem isn't unique to non-alcoholic beer, but without the hops flavours masking it, it's more noticeable. As we discussed when we were carbonating cocktails, the process of adding CO2 to drinks doesn't just add bubbles, it adds carbonic acid. Carbonic acid has a sour—some would say metallic—taste. It tends to be even more noticeable when injecting CO2 directly into the brew, though it can still be present when using starter yeast and sugar.

 

Conclusions

The old adage that alcoholic beer is not universally disgusting doesn't hold up anymore. Yes, many of them still taste like tonic water with some mud in it, but thankfully, there are exceptions. Clausthaler Golden Amber (German) is full-bodied and tastes remarkably like a real beer. Buckler (made by Heineken) actually has a lot of complexity for an NA beer. Kaliber (made by Guinness) is sweet and nutty; it's a bit richer than most of the others. Even O'Douls Amber (made by Budweiser) is pretty good. In terms of flavour, I'd rather drink most of those NA beers over most of our macro-brewed light beers.

The point is that even if they aren't as good as a good regular beer (and they aren't), they are good for what they are, and they aren't something you should be embarrassed to order. They're a hell of a lot better than a DUI. They're also a lot better for you than drinking a soda. As we said, there are a lot of solid reasons to drink non-alcoholic beer. Whatever your reason for ordering one is, we hope we've given you enough knowledge to shut down any smartass detractors next time you're out.

Image credit: Shutterstock/Sergey Peterman