If lumps form in milk, we say that it has curdled. Most people automatically think curdled milk has gone bad but fresh milk can curdle too, under certain conditions.
This process of making milk curdle is deliberate and desirable for making yogurt and cheese… but it’s definitely not what you want if you’re making cocktails for a group of friends!
What Happens When You Mix Milk and Alcohol?
Milk can easily curdle in alcohol.
This happens because alcoholic spirits are weak acids. When you add alcohol to milk, it lowers the milk’s pH value, causing it to curdle.
To understand this process, you should know that milk is made of fats, proteins, and sugars.
Normally the protein molecules in milk float around freely and independently. If you lower the pH value of milk – by adding an acidic ingredient like citrus juice or alcohol – these protein molecules stop repelling each other and begin to stick together and the milk curdles.
Probably not the result you’re looking for when you’re making a batch of cocktails!
How Do You Keep Milk From Curdling in Alcohol?
The secret to keeping milk from curdling in alcohol is to choose a dairy ingredient with enough fat content to keep the milk solids from coagulating. It’s the fat in dairy products that keeps them emulsified.
The fat content in regular 2% milk isn’t high enough. Low fat milk will curdle in alcohol.
Half and half (or half cream, if you’re in the UK) contains 10% fat, which is enough to keep your cocktail emulsified. Just make sure you stir your cocktail while you add the cream.
Heavy cream, or table cream, with 18% fat is ideal. You can safely combine heavy cream with alcohol and it won’t curdle.
How to Make a White Russian Without Curdling the Milk
A White Russian is a cocktail made with vodka, Kahlúa (a coffee liqueur), and cream served over ice.
Although this drink has been around since the mid-20th century, its popularity surged in the 90’s due in large part to the charismatic central character “The Dude” in The Big Lebowski.
What’s the secret to making an amazing White Russian? Use cream instead of milk.
Just pour some vodka, Kahlúa, and cream into a rocks glass with ice then give it a stir and you’re good to go!
If you want to make White Russians at home, here’s the recipe:
- 1 1/2 ounces of vodka
- 3/4 ounce of Kahlúa
- 3/4 ounce of cream
- Pour the vodka and Kahlúa into a rocks glass over ice.
- Add the cream.
- Stir well and serve.
If you want to take this drink to the next level, try adding a teaspoon of vanilla extract or chocolate syrup!
Suggested: Check out these articles for more drink recipes!