Why Does Plant Milk Curdle?

There are some benefits to working from home during lockdown, but the quality of the coffee isn't usually one of them. If curdled plant milk is a problem for you at home, here's some handy hints!

It’s pretty disappointing when the plant milk in your lovely cup of coffee ‘splits’ and leaves you with a floating constellation of curds.

It happens when the acidity in your coffee causes the proteins in the plant milk to denature.

Why doesn’t this happen in dairy milk? Cow’s milk contains phosphates which act as a acidity buffer and neutralize some of the acidity in coffee.

Tips to Avoid Plant Milk Curdle

Here are our top tips for avoiding this unpleasant situation:

• Use a coffee that is less acidic. In general lighter roasted coffees are more acidic than darker roasted coffees and are more likely to curdle your plant milk.

• Don’t make your coffee super-strong (this concentrates the acidity).

• Use plant milk that’s specifically formulated for coffee (e.g. a ‘barista’ product). These will often have natural acidity buffers included to reduce the splitting.

• Allow your coffee to cool a little before adding milk and add the coffee to the plant milk rather than the milk to the coffee.