Getting started
Do you want to be able to create ice cream recipes that are predictable and have the texture, softness, body and sweetness that you like?
Do you want to be able to tweak and change a recipe and not have it fail on you?
All good ice cream recipes are well balanced meaning that all the ingredients are there for a reason. So you can not just change it without consequence. You can not reduce the sugar and expect the consistency to be the same. You can not replace the cream with something else. Ice cream is chemistry and to modify or create a recipe you need to understand some of the basics of ice cream science.
This is my take on how to get started.
What do you need?
You need a compressor style ice cream machine. It will be much more fun and the ice cream will be much better. Ok, you actually don’t need this but it is highly recommended.
You need a scale to be able to weigh your ingredients. Forget the volume measurements start weighing your ingredients.
You need the following ingredients for your ice cream base. With this mix of ingredients you have great control over sweetness and consistency.
Milk
Cream
Skim milk powder (SMP)
Sugar (Sucrose)
Dextrose
Egg yolks
Stabilizer
Ratios
So, what do these ingredients do and how can you change the relative amounts to produce different results.
First we need to look at the ratios of your ice cream. The most important are.
Butterfat
MSNF
Total Solids
PAC
POD
Butterfat – This is the fat content from your milk and cream.
MSNF – This is the proteins in the milk, cream and SMP. It has great water controlling properties.
Total solids – This is everything that is not water.
PAC – This is the freezing point depression factor. This basically controls the softness of your ice cream at a certain temperature.
POD – This is the relative sweetness. Basically how sweet your ice cream is.
PAC and POD are mostly controlled by the sugars you add to the ice cream. And by using two types of sugars, sucrose and dextrose that have different properties, you can easily control the PAC and POD.
Stabilizer
Ok, this is somewhat optional but using a stabilizer will make your ice cream smoother and it will store better in the freezer. A stabilizer will thicken the water part of the ice cream and slow down the formation and size of ice crystals. Common stabilizers are egg custard, gelatin, starches and gums. I suggest you buy a commercial ice cream stabilizer OR that you use gelatin by adding one sheet of gelatin per 1000g of ice cream mix.
And when you want to learn more you should read the definite guide to stabilizers.
https://under-belly.org/ice-cream-stabilizers/
Egg yolks
When making ice cream the egg yolks will act as an emulsifier and a stabilizer. Here you can experiment and I suggest you use between 2-6 egg yolks per 1000g (3% – 10%). I don’t like egg yolks you say! Ok, many people want to make egg free ice cream for different reasons. Egg yolks can dampen flavours and has its own taste. If you don’t like to use egg yolks I suggest you try to use just 1 or 2, you will still get the texture benefits from the eggs but not much of the flavour. If you really really don’t want any eggs just get lecithin and use that instead. Use 1.5g of lecithin per egg yolk.
Milk and Cream
Milk and cream is of course the base of your mix, usually between 70-80% of the total weight. The milk and cream adds butterfat, and MSNF. What you want to do is to change the ratio between the milk and cream to get the butterfat amount that you aim for. There are great tools in the software to calculate what ratio of milk and cream you should use to reach a certain butterfat amount. Because the milk and cream fat content is a bit different in different countries you want to make sure you use the correct fat% for your milk and cream. So a simple example. If you use 400g of milk(2%) and 300g of cream(40%) in a 1000g mix you will get 13.2% butterfat. If your aim was 15% butterfat you would change this to 351g milk and 349g cream.
SMP
The skim milk powder is very important, it binds water and adds body to your ice cream. You will use this to balance the MSNF and the Total solids of your ice cream. I usually aim for about 8-10% MSNF. Just add SMP until you reach this.
Try to not add more than 10% SMP. Because the SMP can absorb a lot of water it can give your ice cream a sandy texture if you add too much.
Sugars
You will work with two different sugars. Normal table sugar sucrose and the sugar dextrose. Dextrose is only 70% as sweet as sugar but it has almost twice the freezing point depression. So, by combining these two sugars in different ratios you can control the sweetness and the softness of your ice cream. Follow these rules to manipulate the sugars.
Sweetness ok but consistency too hard
Increase dextrose and decrease sucrose, maintain POD and increase PAC
Sweetness ok but consistency too soft
Increase sucrose and decrease dextrose, maintain POD and decrease PAC
Consistency ok but too sweet
Decrease sucrose and increase dextrose, maintain PAC and decrease POD
Consistency ok but not sweet enough
Decrease dextrose and increase sucrose, maintain PAC and increase POD
And when you want to learn more read this very good post.
https://under-belly.org/sugars-in-ice-cream/
Total solids
Finally a note on total solids. The total solids is everything in your ice cream that is not water. Making smooth ice cream that is not icy means you need to control the amount of free water in the mix. When making ice cream at home we are at a disadvantage to commercial ice cream making because our ice cream machines are not as good. We can not freeze our ice cream fast enough and we can not freeze our ice cream fast enough after churning. The faster you can churn your ice cream the smoother it will become and the ice crystals will be smaller. To handle this at home we can make sure we chill our base properly before churning and that we pre-freeze our ice cream machine before churning. All to minimize the time it takes to churn our mix.
We can also aim for a high total solids amount. I suggest you aim for 42%-50% total solids.
Example
This can be a good starting point. This will make an ice cream with.
Butterfat 15.1%
MSNF 8.8%
Total solids 46.3%
PAC 283.8
POD 195.5
The freezing point is -3.7 C, 25.3 F meaning it will be quite soft out of the freezer.
| Ingredient | Weight (g) | Amount (%) |
|---|---|---|
| Milk(2%) | 350.0 | 34.97 |
| Cream(40%) | 350.0 | 34.97 |
| Skim milk powder | 40.0 | 4.00 |
| Sucrose | 160.0 | 15.98 |
| Dextrose | 40.0 | 4.00 |
| Egg yolk | 60.0 | 5.99 |
| Stabilizer | 1.0 | 0.10 |
Final words
Ok, this ice cream has no flavour ingredients. This is an ice cream base and to this base you can add different flavours. Use a base like this to add flavours like vanilla, coffee, spices and herbs. It is also perfect as a base for different add-ins.
Fruit and berries ice creams
If you want to make for example strawberry ice cream you need to modify this base quite a lot. Strawberry is 90% water so just adding strawberry will drastically change the ratios and you will get a very hard and icy ice cream. My best advice when making ice cream with fruit and berries is to replace the milk with the fruit. Milk also has approx 90% water. You also need to increase the SMP a little to account for the MSNF in the milk.
Chocolate ice creams
When making chocolate ice cream you need to skip the eggs and reduce the cream. Chocolate has a lot of fat and to avoid a too fatty ice cream we need to balance this by removing the eggs and reducing the cream. We also need to use more dextrose because the fats in chocolate freezes really hard and without using more dextrose the ice cream will be too hard.
Thank you very much
Thanks for such a great and informative piece.
I was wondering if you knew of any reason something like whey protein powder couldn’t replace the skim milk powder in equal amounts? Thanks
From Ice cream 7th edition by Goff and Hartel.
“Dry whey solids are used widely in frozen desserts, because they are relatively
inexpensive sources of milk solids. Federal standards in the US permit substitution
of up to 25% of the MSNF as whey solids. In Canada and the EU, there is no legal
restriction. Whey contains water, lactose, whey proteins, and a small amount of fat
but very little casein. While skim milk powder contains 54.5% lactose and 36%
protein, whey powder contains 72–73% lactose and only about 10–12% protein.
Thus, it can aggravate some of the problems associated with high lactose, viz., lowered freezing point and potential for sandiness. The only advantage of whey powder
is its low cost.”
There are however many whey powder products on the market today so if you like to replace 1:1 you need to check the content carefully.
I have a small gelato side business (self taught) from home and I’ve read countless books all with different information about making gelato. Just this article here has given me more information and understanding than in the last 5 years with all those expensive books. So I wanted to say Thank you.. I’m looking forward to using and understanding this calculator. I’ve been using a pre packaged base from a company and figured it’s time to learn it myself and hopefully save a bit of $$
So I’ll say it again, Thank you
Thank you very much and good luck.