You Should Definitely Consider Adding Sour Cream To Your Gravy
When it comes to gravy, the thicker and creamier, the better. But thickening up a homemade gravy can sometimes take a while, especially if you're trying to reduce a pan gravy by simmering it over time. Additions like cornstarch can help the process along, but these thickeners don't impart much flavor and can affect texture if not added properly. For an add-in that both thickens and enhances flavor, turn to a versatile, dairy-forward ingredient: sour cream.
Sour cream is a common add-in for thickening soups and sauces, but it can also be stirred into gravy for a touch of tang and a smooth, creamy finish. When adding it to your gravy, add a dollop and whisk it in as the gravy nears boiling, but lower the heat to a simmer afterward; this prevents the sour cream from curdling in the intense heat. The result is a deliciously velvety gravy with a touch of acidity for depth of flavor.
Why sour cream makes a perfect gravy thickener
Sour cream comes from a mixture of cream and lactic acid culture — a form of bacteria that begins the fermentation process in various different types of foods, including buttermilk and yogurt. The fermentation process thickens the cream and adds that characteristic tart, acidic flavor to it. Unlike homemade sour cream, store-bought sour cream may also contain some additional thickeners to stabilize the product and allow for low-fat and non-fat varieties.
Between the natural creamy texture of the sour cream and the extra fat content (which also acts as a thickening agent), adding 1 to 2 tablespoons of this product will impart a smooth and rich texture to your gravy. The thicker the dairy product, the more texture it will provide: compare milk to cream to sour cream, and sour cream will get the job done most efficiently. The lactic acid in the product also imparts acidity, which can be a welcome flavor foil to the rich, heavy meat flavors that are often present in gravy.
What to do if your sour cream gravy curdles
Simmering your sour cream-infused gravy on low heat is the best way to ensure it won't curdle in the pan, but if you accidentally overshoot your temperature, there are still ways to save the day. Just like milk and cream curdling in tea, cold dairy can curdle instantly if it meets something too hot; the protein molecules in the sour cream clump together under these conditions and create unsightly lumps in your gravy. Heating the dairy slowly combats this, but if the damage has already been done, you don't have to pitch your hard work just yet.
One option: Pour your gravy through a mesh sieve. This will remove any larger clumps from the curdled sour cream; the other smaller clumps can be whisked out with a vigorous stir. Another way to fix a gravy with curdled sour cream lumps in it is to try blitzing it with an immersion blender. This breaks up the larger clumps and gets everything nice and silky smooth.