How to Adjust the Fat Content of Any Cream

A Helpful Guide for Making Double Cream at Home

Are you a dairy enthusiast? If so, you might want to read today’s post to expand your dairy knowledge, but mainly so that you too can make your own double cream!

One of the best things I learned this past month was understanding how to adjust the fat content of dairy cream.¹ I’m serious! Take a look at the fat content of the cream at your local stores, it is a pretty narrow selection, and those prices. Wouldn’t it be great to skip past that nonsense?

This skill is especially exciting and useful for any home ice cream maker who has been wanting, craving, to make ice cream and gelato recipes from books published solely in the UK.

The vast majority of ice cream recipes published in the UK (both in print and online) tend to use double cream. What we in the US might not know is that double cream has 50% fat content! Yes, you heard me correctly. Sadly, this high-fat creamy dairy goodness is something that the majority of us outside of the UK don’t have easy access to. The heavy whipping cream we have here in the U.S. is most commonly at 36% fat, although I have found a couple of brands that are around 40% fat. You can find imported UK double cream at specialty stores but the insane price-tag makes it prohibitive for most folks especially in the quantities you need for ice cream.

Now the crazy part. All you need to adjust the fat content of your cream is a little time and patience, nothing else. Well, the power of evaporation through application of heat I guess, and a little math.

I picked up this technique and learned the formulas from Nick’s super helpful YouTube channel, Polar Ice Creamery. He has a whole video, called The High-Fat Cream Hack You Need to Know, on the process. I strongly encourage you to watch it.

My post is a short summary of sorts of Nick’s informative video with a handful of common conversions I added myself that I think folks who love making ice cream and gelato in the U.S. might find useful in their ice cream endeavors.

Adding this skill to your ice cream making toolbox is liberating, as it opens up new experimentation doors for you to walk through.

Johannes Vermeer, Public domain, via Wikimedia Commons

Quick Overview of the Process:

One of my favorite ways to learn something new is by reviewing and then doing a bunch of examples. So let’s go over the two part process by working through an example together.

Don’t forget to read the secret Part III to learn how to figure out the exact amount of cream you need to start with to make a specific amount of new fat content cream. This is very useful if you want to make an exact amount of double cream to make a specific recipe.

Part I: MATH

As with baking, ice cream involves a lot of math. Lucky for us, today’s math is relatively simple.

Here are the things we need to know in order to convert our cream from one type of fat content to a different one:

• The fat content of your cream:

  • Let’s use 36% (this is by far the most common fat content for the majority of heavy whipping cream brands here in the U.S.). You can of course do this with any fat content percentage!

• The fat weight of your cream:

  • You can figure out the fat weight of your cream by multiplying the fat content by the total weight of heavy whipping cream you have on hand. Let’s say we have a total of 500 grams of heavy whipping cream.

    • 0.36 x 500 grams = 180 grams

    • The fat weight would then be 180 grams

• The water weight of your cream:

  • You can figure out the water weight of your cream by subtracting the fat weight from the total weight of heavy whipping cream.

    • 500 grams - 180 grams = 320 grams

    • The water weight would then be 320 grams

• The final fat weight of our newly desired fat content cream:

  • You can figure out the final fat weight by subtracting the weight of evaporated water from the total weight of your heavy whipping cream and then multiplying that number by the desired fat content. For our example that would be 50% of the total weight of cream after evaporation.

    • 0.5 (fat content) x (500 grams (total heavy cream weight) - x (weight of evaporated water)

    • Actual equation: 180 (fat weight from above) = 0.5 x (500 grams - x)

  • We have a tiny problem, we need to solve for x (the weight of evaporated water). So how do we do that? Let’s give it a go using the above equation.

    • Example of how to solve for x using the above equation:

      • 180 grams = 250 grams - 0.5x

        • you need to multiple 0.5 by 500 grams to get the 250 g

      • 0.5x = 250 grams - 180 grams

      • 0.5x = 70 grams

      • x = 70 grams / 0.5

      • x = 140 grams

• Now that we have the weight of evaporated water, 140 grams, we can figure out how many grams of reduced heavy cream we need at the end of evaporation to have achieved our desired fat content.

  • 500 grams - 140 grams = 360 grams

  • We need to reduce our 500 grams of 36% heavy whipping cream to 360 grams of 50% fat content cream.

Part II: COOKING

Once you get the math out of the way, all you have to do is cook down or evaporate the excess water from the cream over a low and gentle heat until² you reach the reduced weight of your cream. Following the above example we now just need to reduce our cream from 500 grams to 360 grams, which means we need to evaporate a total of 140 grams. This will take anywhere from 30 to 40 minutes so keep your eyes on the weight and less on the clock. It is very important to not boil your. And make sure to stir the cream every 5 or so minutes just to keep the cream from scorching.

To make things way easier for myself, before the cooking step begins, I always record the weight of my pan so that I can very easily tell when I have reached the desired level of evaporation or the exact gram amount of cream that I need by just putting the pan on my scale. No worries if you don’t have a scale or a robust enough scale, you can just pour the cream into a container and measure how much liquid you half reduced until you have reached your desired weight.

If you do have a scale, here is how it plays out. If my pan weighs 900 grams and I add 500 grams of heavy whipping cream, that gives me a total weight of 1,400 grams. I know that I need to reduce the cream weight down to 360 grams. I then subtract the difference from the total weight, 1,400 grams - 140 grams = 1260 grams. This way, all I have to do to see if I reached the desired weight is place my pan on my scale instead of pouring the cream out to measure the amount of liquid left in the pan. When the scale reads 1260 grams, that’s when I know it is done and I can take the pan off the heat, strain the cream through a fine mash sieve, cover it with plastic wrap (directly touching the surface), let it cool slightly, and store it in the fridge.

Common Conversions:

In the examples below, I am showing my work for figuring out how much water I need to evaporate or by how much I need to reduce the initial cream amount to achieve the desired fat content if I am starting with 500 grams of cream.

Example 1: 40% heavy whipping cream to 50% fat content cream

• 0.4 x 500 grams = 200 grams

• 200 grams = 0.5 x (500 grams - x)

• 0.5 x 500 grams = 250

• 0.5x = 250-200

• 0.5x = 50

• x = 50/0.5

• x = 100 grams (the amount of water I need to evaporate)

• 500 grams - 100 grams = 400 grams (the total new weight of cream after evaporation which will now be at 50% fat)

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Example 2: 36% heavy whipping cream to 48% fat content cream

• 0.36 x 500 grams = 180 grams

• 180 grams = 0.48 x (500 grams - x)

• 0.48 x 500 grams = 240

• 0.48x = 240-180

• 0.48x = 60

• x = 60/0.48

• x = 125 grams (the amount of water I need to evaporate)

• 500 grams - 125 grams = 375 grams (the total new weight of cream after evaporation which will now be at 48% fat)

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Example 3: 40% heavy whipping cream to 48% fat content cream

• 0.4 x 500 grams = 200 grams

• 200 = 0.48 x (500 grams - x)

• 0.48 x 500 grams = 240

• 0.48x = 240 - 200

• 0.48x = 40

• x = 40/0.48

• x = 83.33 grams (the amount of water I need to evaporate)

• 500 grams - 83.33 grams = 416.57 grams (the total new weight of cream after evaporation which will now be at 48% fat)

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Example 4: 33% heavy whipping cream to 50% fat content cream

• 0.33 x 500 grams = 165 grams

• 165 = 0.5 x (500 grams - x)

• 0.5 x 500 grams = 250

• 0.5x = 250 - 165

• 0.5x = 85

• x = 85/0.5

• x = 170 grams (the amount of water I need to evaporate)

• 500 grams - 170 grams = 330 grams (the total new weight of cream after evaporation which will now be at 50% fat)

PART III: How to Calculate the Exact Amount of Cream You Need to Start with to Make A Specific Amount of New Fat Content Cream

Let’s say you need 300 grams of 50% cream for a recipe you want to make!

How do you figure out how much total heavy whipping cream you need to start with? Easy.

Take 300 grams and divide it by 2 (or multiple by .5). As Nick points out in his video, this will give you the total “fat content of the final (cream) reduction at 50% fat content” (Polar Ice Creamery). We are doing 50% for this example but you can do whatever percentage you need. We can do 300 * .48, .40, .65, etc.

Next take 150 grams and divide it by the fat percentage of your starting cream, let’s use 36% for our example. 150 grams / 0.36 = 417 grams.

We now know the exact quantity of heavy whipping cream we need to start with. In this case, we need 417 grams of 36% in order to produce 300 grams of 50% cream. Meaning we need to evaporate 117 grams to achieve the desired new total weight of cream.

So if my heavy bottom pan weighs 900 grams and I add 417 grams of heavy whipping cream, that gives me a total weight of 1,317 grams. I know that I need to reduce the cream weight down to 300 grams. I then subtract the difference from the total weight, 1,317grams - 117 grams = 1200 grams.

That’s it!

The Milkmaid by Lucas van Leyden (Netherlandish, Leiden ca. 1494–1533 Leiden) at the Met.

I hope you find this guide as helpful as I do.

All mistakes are of course my own! If you find a typo or a math mistake please let me know and I will update the post.

Please share your tips and tricks!

I can’t be the only one interested in this topic.

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1. The fat requirements for different types of cream tend to have a pretty broad range here in the U.S. For example, half-and-half can range from 10% to 18% fat content, light cream can be anywhere from 18% all the way up to 30%, and lastly heavy whipping cream has the lowest range from 36% to 40%.

2. The duration of this process will depend on your heat source, how much cream you start with, the fat percentage you are starting from, as well as the fat percentage you are trying to achieve.