Yeast is essential to the making of beer. As such, there are no beers that have not had yeast in them. However, yeast can be filtered out of a finished beer leaving few to no yeast cells behind.
Beer companies often leave yeast out of their ingredient lists which is likely where any confusion comes from. This does not change the fact that your favorite beer almost certainly contains (or used to contain) yeast.
Why Does Beer Use Yeast?
First, a quick overview for anyone unsure why yeast is necessary when brewing beer.
While there are plenty of ways for fermentation to occur, yeast is the catalyst that creates desirable alcohol. In the beer brewing process, yeast consumes sugars present in a liquid called a “wort” to produce ethanol and carbon dioxide.
Other types of fermentation create products that are often not desirable in beer. So the only way for beer to contain alcohol is by using yeast.
Is There a Beer Without Yeast?
While no beer is made without yeast, there is a style of beer made without adding yeast. This statement might seem a little contradictory so let me explain.
Lambic beers are dry, fruity beers that can be tart. It is a complex beer style both in taste and creation. This beer style is made without adding any carefully cultivated brewer’s yeasts, which raises the question of how its alcohol is produced.
In the brewing stage, the wort that becomes beer is left open to the air. This allows the wild yeasts and bacterias in the air to find their way into the wort. Since they have no competition from yeast selected by the brewer they can take over.
This method is called spontaneous fermentation.
Lambics are the closest to a beer without yeast in some senses, but as it is still made with yeast it doesn’t quite meet the requirement. As usual, the beer can and often is filtered to remove the yeast as well as any undesirable cloudiness.
Does Alcohol-Free Beer Contain Yeast?
Since yeast is responsible for the presence of alcohol it seems safe to assume that alcohol-free beer doesn’t contain any. Unfortunately, even alcohol-free beer can contain yeast. Most brewers of this style of beer still use yeast in its creation.
You may be wondering why low to no alcohol beer is made using an organism that produces alcohol. The primary reason is flavor. In addition to its main purposes, yeast also has a large influence on the flavor of a beer.
Of course, it wouldn’t be alcohol-free beer with alcohol present. Once fermentation is complete and the beer flavors have been achieved there are a couple of different ways that brewers remove the alcohol.
In most cases, these processes can also be used to remove the yeast from the beer. So when you get these beers they may not have much yeast if any.
That said, there are a select few alcohol-free beers that aren’t made with yeast. The brewers achieve a beer taste using other methods.
Is There Yeast in Lager?
Unlike a lambic, lagers are made using a cultivated yeast strain. In fact, lagers have an entire style of yeast named after them. The two main styles are lager yeasts and ale yeasts. The differences between the two aren’t pertinent at the moment, however.
Point is, lagers are made using yeast. However, lagers are the most well-known styles of beer. There are plenty of macro breweries that focus solely on lagers. These breweries aim to make the best beer for the largest audience and have been successful with lagers.
Popular beers such as Budweiser, Stella Artois, and Heineken all brew with yeast before filtering it out of the final product.
A key factor in their success is the clarity that lagers are known for. This results from the way that lagers are made as well as the extensive filtering they go through. Because of this, it is highly unlikely there is any yeast left in a commercial lager.
Does Guinness Have Yeast?
If lagers have no yeast in them because of how clear they are, what does that mean for darker brews like Guinness? It is certainly harder to check the world-famous Guinness for clarity by just looking at it.
No need to fear, however. Guinness is also heavily filtered. Though you can’t tell be looking at it, there is no yeast haziness in Guinness. It is still brewed with yeast of course.
Up until recently, Guinness was filtered using a material gathered from fish bladders called isinglass.
Is There Any Alcohol Without Yeast?
At this point, you may be wondering the above question. If even alcohol-free beer uses yeast is there any alcoholic drink that doesn’t? It turns out that you can produce alcohol without yeast, but you probably won’t want to drink it.
Certain strains of bacteria, such as Zymomonas mobilis, can consume sugars to produce alcohol just like yeast. The biggest issue with this is that these bacterias will also produce undesirable flavors often referred to as off-flavors.
Another problem is that, unlike many yeast strains, the bacteria that can produce alcohol can’t use a sugar called maltose to do so. Maltose is one of the most common sugars present in the wort used to make a variety of alcohol.
So most commercial alcohol is made using yeast, but again that doesn’t always mean there is yeast in the final product. Most hard alcohols are filtered or distilled. Vodka is a great example of this. There shouldn’t be any yeast in the vodka you buy at a liquor store.
Why Would You Want to Avoid Yeast in Beer?
All of this concern over the presence of yeast might seem unnecessary, but there are some good reasons to look out for it.
Though uncommon, it is possible to be allergic or intolerant to yeast. Such an allergy can result in a multitude of unpleasant symptoms.
Other reasons for avoiding yeast can be as simple as not liking the taste—though as yeast is filtered out of most beers before they reach your glass, it's usually just a case of avoiding certain types of beer with the most yeast, and sticking to ones you prefer instead.