Beer and Milk - Does it Mix or Will it Make You Sick?

If you ever mixed all of the sodas from a soda fountain together, you know that there are some interesting combinations in the world of drinks. You also know that sometimes two things that taste great on their own are absolutely terribly together. So which is true of milk and beer – a natural mix, or a stomach-curdling combination?

Many people find the beer-and-milk combination pleasant when done correctly, like in a beer nog or Guinness milkshake. Done incorrectly, the beer will curdle the milk or make it difficult for your body to absorb the milk, leading to diarrhea. Milk stouts do not curdle because the lactose lends creaminess, but there is no actual milk used.

Keep reading to discover ways to mix beer and milk properly as well as options for how to mix the two.

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Is milk and beer a bad mix?

There are two sides to this question. There’s the objective and the subjective.

Combining beer and milk as a flavor is up to you and your taste buds. Objectively, however, there are better mixes out there that aren’t as likely to curdle. Either way, it is a mix you can drink as long as it’s not in excess.

With a world as wide and varied as ours, you can almost always find at least one person who likes something. Beer and milk might sound like a horrible combination to many, but there are a fair amount of people who enjoy it.

There is all manner of ways to combine the two. They can be enjoyed separately, one after the other, together as a cocktail, or mixed in a milkshake.

The problem is that it can be a volatile mixture. Beer can and will make milk curdle. It can happen in a multitude of different situations.

Drinking curdled or curdling milk doesn’t sound like a great time to me. It could certainly make someone hurl. Even the thought of milk curdling can be enough to send someone running for a toilet.

If done correctly and with a strong constitution, beer and milk can be a tasty combo. But milk – like beer – can be unpleasant in large quantities. The most milk you should drink in the following scenarios is a glass, maybe two.

Does beer make milk curdle?

Say you’ve decided to try it drinking beer and milk together out of curiosity. You’ve grabbed a beer – let’s say a Coors Light – and a glass of 2% milk. You mix them together to see what happens.

More than likely, the beer will make the milk curdle. The fats that protect the proteins in milk aren’t there in 2% milk. The acidity of the beer will cause the unprotected proteins to clump up and begin curdling.

It’s all about the pH levels. Between 7.1 and 14 is alkaline while 6.9 and below is acidic. Seven is right in the middle and is labeled neutral. Coors Light, like all beers, is acidic. Most beers are around 4.1 to 4.6 on the pH scale.

Acidic solutions curdle milk through the effect they have on the micelles that make up milk. Micelles are small collections of proteins called casein.

These clusters all have a negative charge and since charges of the same polarity repel each other, the clusters are evenly dispersed. That negative charge is removed by acidic solutions which causes the micelles to gather in larger and larger clusters.

As with most things, there are multiple factors that affect this reaction. The most obvious factor is the age of the milk. It is quicker to curdle if it is old. Beer on the other hand can become less acidic as it gets older. Even so, fresh beer is better.

The type of milk can also affect the likelihood that it curdles. Our example milk is the most likely to curdle because it is only 2% fat.

The fats in the milk provide natural insulation for the protein clusters. More fat equals better protection. This is why heavy cream is less likely to curdle.

Will beer make milk curdle in your stomach?

The only difference between this scenario and the last is that you are mixing the two in your stomach as opposed to a glass.

Beer can still curdle milk in your stomach. The same reaction happens with the same components. However, milk will curdle even without a beer in your stomach because of your stomach acid.

Since milk curdles in the presence of an acid, and your stomach contains gastric acid, milk will curdle eventually. Beer may speed up that process, but it will occur either way.

Will milk and beer give you diarrhea?

Even though the fact that milk curdles in your stomach doesn’t sound appetizing, the milk probably isn’t the cause of diarrhea after drinking.

It is more likely that the beer is what’s causing diarrhea. Alcohol disrupts the digestive process when enters your intestines. Milk can make diarrhea worse, but unless you are lactose intolerant it usually doesn’t cause diarrhea.

Alcohol has a large impact on the body when it is absorbed. There are the more obvious effects that everyone knows, but there are also the effects on your digestive system.

When alcohol is absorbed in your intestines it can make it harder to absorb all of the water in your waste, which can result in diarrhea. The strength of this effect depends on how much you drink and how well you’ve slept in recent nights.

In this case, milk won’t cause diarrhea. Drinking it at the same time as beer shouldn’t affect you too terribly. The alcohol could make it harder to properly digest milk, but not in a noticeable way.

When you have diarrhea, you should avoid dairy because you can develop a slight intolerance while it persists. If this happens, milk can cause extra gas and a bloated feeling.

Can you drink milk after drinking beer?

So if that’s what happens when you drink milk and beer at the same time, what about when you drink one after the other?

Drinking milk after a couple of beers is worse than drinking milk before beer. That said, as long as it’s just a glass, it shouldn’t affect you any more than the beer will if you drink too much.

As mentioned above, alcohol messes with your digestive tract. Since your body prioritizes metabolizing alcohol, other foods and drinks can take longer to digest.

Milk in this situation shouldn’t cause any really noticeable issues. However, since the alcohol has had some time to absorb, it may give you diarrhea which is made worse by milk.

It would be best to wait until after the alcohol leaves your system if you aren’t feeling well. This can be anywhere from 6-12 hours depending on how much you drink and a couple of other general factors.

If you aren’t too badly affected by alcohol you can drink milk sooner without too many adverse effects.

Can you drink milk before drinking beer?

Drinking milk before an evening of drinks is something you may have heard recommended. There’s an urban myth that drinking a glass of milk will coat your stomach and slow down the absorption of alcohol.

You can drink a glass of milk before beer with no unfortunate side effects. This can be done a couple of hours or just before drinking beer.

Drinking milk before drinking beer is better than drinking it at the same time or afterward. The milk will be digested normally and that will be that.

The urban myth side of this is a bit inaccurate. Drinking on an empty stomach is a great way to throw up. Drinking milk won’t really line your stomach to prevent this. But eating beforehand will slow down the absorption rate of alcohol.

Milk would in theory do the same with enough of it. The problem is that you’d have to drink so much milk you’d have no space for beer. So just one glass of milk before drinking beer won’t help you much in regards to reducing the effect of the beer.

If you happen to really enjoy the taste of milk, feel free to drink a glass before going out to the bar.

What about milk stouts?

Milk stouts are a whole other beast. Despite what the name indicates they are not a mixture of milk and beer. Not exactly.

Since milk stouts only contain lactose from milk and not actual milk they won’t curdle in the presence of an acid. They can be enjoyed just like any beer. As long as you aren’t lactose intolerant or drink too much, they won’t make you sick.

It is just the proteins in milk that cause it to curdle when they are denatured. A milk stout won’t have these present.

Milk stouts will have a nice sweetness provided by the lactose that doesn’t get fermented.

Are there beer and milk cocktails?

As it is there aren’t very many cocktails that involve beer and even less that mix beer and milk.

Beer and milk cocktails do exist, but they aren’t very common due to the fact that it is not a common palate that enjoys milk and beer together.

One such beer and milk cocktail is the beer nog. This drink is just like eggnog, but with a milk stout. There is also a beer and milk mixed called bilk. Bilk is roughly 70% beer, 30% milk.

It is entirely likely that there are other beer and milk cocktails that have been made. It is even more likely that these drinks were made once and never mentioned again. Whatever the case, there aren’t very many beer and milk drinks out there on the internet.