What is the lowest fat you have gone and still had creamy homemade ice cream?
acgold7 is right. You can go as low as 0% fat and still have a creamy texture - thanks to stabilizers.
Stabilizers thicken the final product and make it smoother by preventing the formation of large ice crystals. These two things combined are what gives a frozen dessert is creaminess.
Common, 100% natural stabilizers come from either animal sources or plant sources. The most common are:
Plant: Carrageenan, guar gum, and locust bean gum
There is absolutely nothing wrong with using stabilizers, and many things right with using them. They are a natural ingredient just like milk or sugar.
The subthread above has gone way off topic, so the clear straight answer is: theoretically, zero, if you are willing to add a lot of other stuff, namely, eggs and/or other starches, thickeners and gums, the way the manufacturers of nonfat "ice creams" do.
In addition to eggs, some of the more natural additives commonly used would include
Locust Bean Gum
Nonfat Dry Milk Solids
Corn Syrup Solids
Karo Syrup instead of some of the Sugar, or Invert Sugar, Maltose or Glucose Syrup used similarly.
Some less natural ingredients would be mono and diglycerides and polysorbate 60 and 80, commonly found in whipping cream.
Some people like to make Ice Cream using Evaporated Milk or Sweetened Condensed Milk, but I believe these run about 8% milkfat.
If you are trying to make ice cream out of nothing but pure milk, sugar and flavorings with a little cream and nothing else, you will likely be disappointed with the results unless you are above about 10% milkfat. But your tastes may vary.
Well, no, not only milk. Many gelati do have some cream, and if they don't, they have eggs, or corn starch, and huge amounts of sugar to compensate, and are served at a much warmer temp than American or French Ice Cream. So you will have to experiment quite a bit and read a lot to figure out what works for you. If you tried to serve gelato at the same temp as ice cream it would be hard or icy and crumbly.
Of the 20 top gelato recipes I've collected from the web, 12 have copious amounts of cream as well as milk. The 8 that don't all have added starches (flour or cornstarch) or gums to achieve smoothness. All have eggs and all have much more sugar than their ice cream counterparts.
Just for reference, anything less than 10% and the gubmint says you can't call it Ice Cream -- it's Ice Milk.
Some gelati may use cream or eggs, but the traditional recipes are milk only, which is why they usually have much lower fat content.
While I can appreciate the statistical value of relying on "20 top" recipes that you've collected (actually, I don't even know what "20 top" means) that doesn't make the recipes the standard for gelato.
This is a common misconception but a little research goes a long way. Every "Definitive" text on the subject -- and I have and have read them all -- specifies eggs in the mix, and Leibovitz, the current darling, specifies cream in 100% of his Gelato recipes in his book, and he notes that "Gelato" is just Italian for Ice Cream.
So dismissively saying "some" is just wrong.
Nevertheless, this is easy enough to test at home, and should be fun trying. Be sure to report back.
("20 top" = Most Hits filtered by Highest Feedback filtered by Authoritative Reputable Sources, i.e. Not Tyler Florence.)
Hate to flog a dead horse, but there's a reason gelato is not called ice cream (and the word "gelato" is literally "frozen" but has become interchangeable with "ice cream") - that reason is simply fat content. Gelato traditionally falls appreciably below 10% and can go as low as 4% (which is essentially whole milk). You can add cream and you can add egg yolks as the flavors may require, but it's not an essential ingredient in all gelati.
As for adding cornstarch, that doesn't really add fat, so as far as being responsive to the original poster, I would still maintain that 4% is an effective low-end. As for "huge amounts of sugar" that's also a misconception.
Finally, as for the "current darling's" take on gelato, he clearly understands that you can make a traditional gelato with milk.
"Matt, aka Matteo…aka, Tèo…learned his craft in Florence at Vivoli, and his gelato is the real deal. You won’t find him in the back dumping mixes into a machine.
His gelati are made fresh daily and low in fat; most of the flavors he churns up are made with whole milk, no cream or eggs. "
>>>Finally, as for the "current darling's" take on gelato, he clearly understands that you can make a traditional gelato with milk.<<<
And, as I noted above, loads of cornstarch, which is a stabilizer and thickener.
You can add whatever you want to your gelato to make it simulate creaminess, and I never said it couldn't occasionally be made without cream, but the OP was about how little cream you can use in ice cream and still have it come out creamy. At a certain point, no matter how much other stuff you add, it ceases to be ice cream.
And if you use just milk and no other thickeners/stabilizers, it's just ice milk.
And if you have an argument over the definition of gelato, argue with Leibovitz, not me. I was just quoting him.
2 tablespoons of cornstarch in 3 cups of base isn't "loads." The question was "how low can you go" and 4% is generally recognized as the low end. "Ice milk" and "ice cream" are regulatory definitions, not absolutes. There may be a legal distinction between 4% fat and 10%, but it's not what the OP was looking for.