Why does liquid coffee creamer coagulate in iced coffee?

by Lisa
(Michigan)

QUESTION:

I am not a big coffee drinker, but I do like iced coffee on occasion. When I brew the coffee (single serve k-cup) and put the liquid creamer in, it blends fine and makes great, smooth coffee.

But then, when I put in the ice cubes, the previously fully blended liquid creamer starts to chunk up and I end scraping most of it out of the coffee. What is causing this coagulation? I'd really like to have iced coffee, but I'm dumping out most of it out, and it's getting expensive.

Thanks for any info...

Lisa


ANSWER:

Lisa, hi

Creamers coagulate or curdle when there is a sudden change in temperature. This is true of creamers in coffee as well as with soy milk, almond milk and so on. The proteins in the creamer react to the change in temperature by coagulating or clumping.

Artificial creamers include an ingredient called dipostassium phosphate, which helps prevent coagulation.

In your case, the key is to minimize the temperature difference between the coffee and the ice cubes. In other words, let the coffee cool for a little longer before adding the ice.

Alternatively, add the ice to the coffee before you add the creamer. Again, let the coffee cool for a while before you add the creamer.

What I do when I want some iced coffee is make a full pot of coffee, let it cool and then store it in the fridge. Each day I then pour myself a glass of refrigerated coffee and add cream and ice just before I drink it.

I hope this helps a little!

Read more about making iced coffee at home.

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