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


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.
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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