The Essential Step To Prevent Cream From Curdling In Soup

There's nothing like a hot bowl of soup on a cold night to get you feeling warm and cozy, especially if it's a hearty bowl of cream soup. But if you're feeling ambitious enough to make your own soup from scratch, perfecting that silky smooth bowl of creamy soup can be a bit of a tricky thing. That's because cream soup includes dairy (obviously), which can be a bit temperamental when heated.

As First for Women explains, heat and acidity can cause dairy products -– and even some non-dairy milk substitutes like soy milk -– to separate and curdle, which, while not necessarily unhealthy like the curdling that occurs when milk goes bad in the fridge, can taste bad and seriously throw off the texture of your coffee or soup.

Science Notes remarks that this happens because the heat causes the proteins and the water in the dairy products to separate, with the proteins lumping together, watering down your soup and creating unwanted lumps. Because of this risk, you need to be cautious about when and how you add your cream or milk to your soup so that you get the desired texture for your warm meal.

Avoiding separation

The first step to avoiding curdling dairy products in your soup is to not add them to your pot or slow cooker immediately. Essentially, the longer and hotter they cook, the more likely these ingredients are to start separating. While All Recipes explains that different ingredients run a higher risk of curdling than others -– heavy cream, for example, is unlikely to curdle from heat alone, but it can if it's cooked with high-acidity ingredients like wine or tomatoes -– you're still better off waiting to add it in until later, as noted in this Tasting Table Recipe for shrimp bisque.

While heavy cream may not curdle easily, lower-fat dairy products, including milk, half-and-half, and sour cream can easily go funny when mixed into a hot pot of soup. To avoid this, Recipe Tips stresses that you should never add these ingredients to a boiling soup. Turn the soup down to a simmer before adding the ingredients, then leave it on low heat until finished.

Additionally, it may be wise to gradually heat your cream products before adding them, so the change is less drastic. Chatelaine recommends warming even heavy cream before adding it to soup to prevent curdling, though no specific method is suggested. Meanwhile, Recipe Tips notes tempering the cream by mixing in small amounts of the hot broth to the cream can bring it up to temperature, as well as adding a bit of flour and water to the cream or milk to stabilize it.