Here’s how these two dairy products stack up with each other.
She points out four particular ways in which heavy cream and buttermilk distinguish themselves from each other.
What Is Heavy Cream?

Credit:Caitlin Bensel; Food Stylist: Torie Cox
It can be whipped or added to recipes to create a creamy texture.
What Is Buttermilk?
Traditionally, buttermilk is the dairy liquid that’s left after churning butter made from cultured or fermented cream.
Today, cultured buttermilk is made from pasteurized homogenized milk with added bacteria to mimic naturally occurring ones.
This is a result of fermentation.
Buttermilk is cultured milk, meaning that it contains active (good) bacteria.
When To Use Buttermilk Vs. Buttermilks tanginess can also counteract the sweetness of baked goods, providing a valuable balance.
Can I Substitute Buttermilk For Heavy Cream?
In some instances, buttermilk is a greatsubstitute for heavy cream.
If the buttermilk is used in conjunction with baking soda in a recipe, swapping won’t work.
The baking soda needs to react with the acid in the buttermilk.
Buttermilk can’t replace heavy cream in recipes where it needs to be whipped.
The California Dairy Press Room and Resources.Buttermilk.