Homemade Sour Cream

Directions

• Before We Start

  Cultures: Most store bought sour creams have live cultures in them. We recommend getting a sour cream you like so the nuanced flavor is similar to it. You can also use buttermilk, but we think sour cream cultures makes the best sour cream.
  Adjusting Sourness: The longer you let it sit out, the more the cultures have time to create the lactic acid that makes it sour. If you want it to be less sour, 24 hrs is good. 56 hrs will be quite sour. 36 hrs is a happy medium and is the general timing we recommend.
  Speeding Up the Process: If you need to make it fast, there are two steps you can take. One is to warm it up to about 80 degrees using a fermentation chamber or seedling mat. This helps the cultures thrive. Also, doubling the amount of sour cream can speed up the process. You effectively double the amount of cultures you start with. If going this route, we recommend checking it after 18-24 hrs.
  Using Seedling Mat: You can buy a seedling mat off Amazon for pretty cheap. They come in handy for raising the temperature of your ferments by about 10-15 degrees. You just set your ferment on them. This is great for kombucha, lacto fermentation, and of course, culturing cream. You can use a thermometer after 5 hrs to check the temp of your fermentation. If it is above 85 degrees, we recommend laying down a trivet or hot pad to keep it below that temp. Ideal temp is 82 degrees. Building a fermentation chamber is another option to have precise temperature control.

• Combine Ingredients

  In a medium bowl or container, combine the sour cream and milk. Whisk together so there are no lumps. This will help distribute the cultures.
  Next add your cream and whisk to combine. Transfer the mixture to a glass or plastic container that is air-tight. Place the lid on the container.
  
  Note: We just do all the mixing in the container we are going to store it in to save on dishes.

• Let it sour

  If not using special equipment, leave it on the counter at room temperature to ferment for 24-56hrs. We recommend checking it after 36 hrs with 42-48 hrs likely being the best timing. The longer you let it sit, the more sourness it will develop. Cultures and home temperatures are different, so the timing is a general guide and not a hard and fast rule. The warmer the environment the faster the ferment will go.
  If using a seedling mat, see our notes in the “Before we start” section. We are looking for somewhere around 78-85 degrees. If using a fermentation chamber, set it to 82 degrees. Our tests on timing used this heat range. 36-42 hrs is likely going to be perfect. 36hrs being less sour, 42hrs being quite sour.
   
  As it sits in the fridge, it will increase in sourness slightly over time, so it’s better to
  
  NOTE: As it sits in the fridge, it will increase in sourness slightly over time, so it’s better to pull it while it is less sour than too sour. The timing is pretty forgiving as well. There is about 4-6hr window before there is much of a recognizable change in flavor, so you don’t have to be super precise here.

• Refrigerate

  Once it has thickened and developed the level of sourness you like, it is ready. You stop/slow the fermentation (souring) process by putting it in the fridge.
  If there is some liquid collecting, you can spoon out that whey, it is also perfectly acceptable to leave it as is.
  
  It will continue to thicken slightly when you refrigerate it, so expect the texture to be a little firmer the next day.