How Can I Prevent Soy Milk from Curdling in My Coffee?

updated Jun 9, 2019
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Q: What’s the deal with the white flakes in my soy milk? I’m on my third fresh carton in a row that has had very fine white flakes, which settle at the bottom of a glass. They would probably be very subtle in a glass of soy milk, but in my iced coffee, they are quite obvious and there’s some texture there.

This has happened to me with Silk brand, Trader Joe’s vanilla flavor, and even in my drinks at Starbucks! I’m wondering whether this is normal to everyone else, and I’m just expressing a preference? My Starbucks barista seemed less than accommodating to re-make my flaky iced latte twice….

Sent by Alannah

Editor: Alannah, unfortunately the acid in coffee has a tendency to curdle soymilk, producing that flaky look. Here’s a post little more info on what’s going on (and be sure to read the comments for some helpful reader tips):

Readers, do you have any tips for minimizing curdling when you add soymilk to coffee? Any brands that seem to work for you?

(Image: Flickr member Mike McCaffrey licensed under Creative Commons)