Why did my creme fraiche turn out runny?

I mixed my creme fraiche (2 tbsp buttermilk, 1 cup heavy cream) in a mason jar and left it, unsealed, for 12 hours, then refrigerated it for four hours. It came out thick like sour cream, and was perfect. The second and third batches I made came out runny, but I used the same measurements, ingredients, and method. Why?

  • Posted by: bryan
  • January 2, 2014


TS January 4, 2014
Bryan - My understanding is that sometimes ultra-pasteurized cream can be more finicky, as in doesn't set up as well, than pasteurized. That may be the problem. Good luck to you!
bryan January 4, 2014
Thanks for the tip, Kate. That could actually be the problem, because the day I made it perfectly I had been baking. I'll leave it out longer this time and see what happens.

Trena, the cream is ultra-pasteurized.
TS January 3, 2014
I think Kate brings up an excellent point. Also, was the cream ultra-pasteurized?
Kate January 3, 2014
Did the temperature in your kitchen change? At lower temperatures, it can take several hours longer to thicken.
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