How to Make Sour Cream at Home

By Megan Wabst

Sour cream—a “cream” that has been slowly preserved, or soured, with an acid to create a thicker, tangy cream—is simple to make at home!

The key is a temperate environment between 67-72° F and an undisturbed 24 hour period to let the bacteria in the dairy do its work.

Learn about the sour cream making process and find a full recipe below!

About Sour Cream Ingredients

There are three key ingredients in making sour cream:

• Whole Milk – full-fat milk has the fat required fat content to create the best curds and to hold more cheese creating cultures.
• Heavy Cream – heavy cream is what gives sour cream it’s thick consistency while lending that flavor that’s perfect for topping things like baked potatoes and tacos.
• Acidity – acidity is needed to cause the chemical reaction (fermentation) that separates the whey from the cream. It helps make the sour cream thicker. Fresh lemon juice and vinegar (white distilled) both provide enough acidity to make this process happen.

Sour cream “start packets” are cultures you can buy, though they can sometimes be hard to find. With those purchased “pre-made” cultures, you can make sour cream out of heavy cream without the need for the full-fat whole milk. 

The Importance of Temperature

When making sour cream, it is crucial to use whole milk and heavy cream that is room temperature. Cold or hot dairy can cause the cream to set improperly or not at all. Aim for baby bottle or warm bath water temperature.

If you’re in a hurry, you can warm the milk and cream (separately) on the stove. This requires very low stove temperatures and a close eye. Ensure you avoid burning the dairy by not allowing either to hit the boiling point. You will likely need to let it cool a bit to get down to room temperature.

Gearing Up

Making homemade cream cheese requires a few common kitchen items. These include:

• Clean jar or container (with lid or rubber band)
• Clean towel or cheesecloth
• Measuring spoons
• Lemon juicer – if hand squeezing, be careful to avoid seeds.

Sour Cream Recipe

Yield: 1.5 cups

Ingredients

• 1 ¼ cup heavy cream (aka whipping cream)
• ¼ cup whole milk
• 2 tbsp lemon juice or vinegar

Preparation

The milk and cream need to be at room temperature (~70-80* F / 21-26* C), so take them out of the fridge and measure out your liquids a good while before planning to make your sour cream. You will also want to make sure your jar and lid are clean and dry.

Directions

1. Pour room-temperature whole milk into clean jar. For this recipe, a 16 oz jar is ideal.
2. Pour lemon juice or vinegar into jar and close lid firmly. Gently shake the mixture until combined.
3. Open the lid, pour in room temperature heavy cream. Close the lid firmly and gently shake the mixture again. Don’t over shake here, we want sour cream not some weird version of butter.
4. Remove the lid (keep it for future storage use). Place a thin towel or cheesecloth over the jar then fasten it with the jar ring or a rubber band. Whatever you use to cover the jar, just ensure it can breathe and ferment into the thick sour cream you’re looking for.
5. Place the jar in a jostle-free and room temperature (around 70* F) environment for 24 hours. Watch for signs of whey settling out of the cream to the bottom of the jar and a thick jiggle from the cream on top when you move the jar.
6. After 24 hours, the cream should be thick. If you want only the thickest part of the cream, spoon the separated cream from the whey at the bottom into another container. If you like a thinner sour cream, stir up the mixture and you can store it in the same jar.

Storage

You can either store the sour cream in the jar you made it in, or in another clean, airtight container. Keep your finished product in the refrigerator for up to 2 weeks.