This guide originally appeared over on Ice Cream Club's tumblr, many, many summer ago. Jonathan Soma gets all credit.
There are a few types of ice cream, but the easiest to work with is Philadelphia style. It’s different from the more-complicated French style because while the French style is based on a custard, Philadelphia style is just milk and cream. Custards are cool and give a richer flavor and texture, but they mean you have to plan ahead. That isn’t so much my style, so let’s stick with Philly.
Here's the general recipe to use for making Philly style ice cream:
2 cups cream
1 cup milk
1/2-2/3 cup sugar
+ flavoring (more on that later)
The cream provides you with milkfat. It’s going to be heavy cream, which is about 36% fat. Milkfat provides smooth texture and a good meltdown.
The milk provides you with milk solids. They improve the texture and enhance the air-holding ability of ice cream. Sure it also has fat, but at 4% for whole milk it isn’t too impressive. Ice cream made just from milk tends to be kind of icy.
I like a ratio of 2:1 cream:milk. You can usually get away with 2 cups of cream to 1 cup of milk without overflowing your ice cream machine.
Next up: sugar. Sugar helps resist freezing, too. You’ll want about half a cup to ¾ cup (I recommend the low end). If you’re using a liquid sweetener you’ll only want to use 75% as much as if you’re using regular sugar. Also! Some people make you go out and buy confectioner’s sugar (powdered sugar), but i haven’t found that it makes much of a difference.
So, your standard ratio is now around 2:1:.5, cream:milk:sugar. If you like mnemonics you’ll notice the numbers halve each time.
Now add a teaspoon of vanilla. Everything is better with vanilla! It just fills everything out, I think.
Now, let’s talk about ingredients!
Pick whatever you want. Look up anything - a random dessert, banana bread, gingerbread, whatever - and pull out the flavorful ingredients, spices and whatnot. Let’s cover how to add them into the ice cream mixture:
Whole things: Let’s say you want to make an ice cream flavored with chiles, or peppers, or coriander. You don’t want them in the actual ice cream, though, just the flavor.
SOLUTION: Combine the ingredients (crushed or cut if needed, to release more flavor) with the cream. Put the cream on the stove until it’s hot, then let it sit for a while (up to an hour). Taste it every now and again to see how you’re doing in the flavor department. Strain out the chilies/pepper/coriander
SCIENCE BACKGROUND: What’s happening is that the flavor compounds are fat-soluble, so they’re combining with the fat in the cream. You want to do this with the cream and not the milk because cream is 36% fat while milk is only about 5%, so the cream is way way better at absorbing the flavor.
Powder things: Cinnamon or garlic powder or stuff like that, you can just mix in with the cream-milk-sugar mixture.
Zestables: Citrus fruits live in this category. You can either slice off the rind, twist it to release some of the oil and steep it (like whole things) or zest it into tiny bits and treat it like powder. Zesting is when you grate it up into tiny bits! If you zest you can also let it steep for a while.
Earlier today I zested an orange and let it steep, but then zested a lime and put it right into the mix and then the machine. No rhyme or reason! Also, be careful - zestable are usually pretty powerful flavorwise, add a little bit at a time and taste often.
Liquid things: Same as above! This includes weird mealy things like very-mashed-up bananas.
Chunks: If you want to put pieces of banana or strawberry or anything like that into your ice cream, don’t put it in yet! They’ll all just sink to the bottom or get mashed up and mix in with everything else instead of staying as chunks. You want to run your ice cream machine for a while, then put them in about 5 minutes before you think it’ll be done.
SECRET TIP: Stick ‘em in the freezer before you put them in! That keeps them from raising the temperature of the ice cream when you put them in.
Sugary things: When adding stuff like honey and molasses you replace the sugar with it, not use it in addition to the sugar. Well, unless you’re really into sweet things.
Swirls: Swirls are a big big secret. Let’s say you make a chocolate ganache (liquidy chocolate, basically), and you put it in at the beginning. The whole ice cream will turn chocolatey, and you won’t get streaks. Put it in near the end? The same thing might happen!
The easiest way to get streaks is to wait until the ice cream is done, then layer the chocolate with the ice cream whenever you’re scooping it into a storage container. It seems like a cop-out, but I promise it’s the best way to go (and no one’ll notice!)
Now you can add your ingredients to the ice cream machine! Make sure it’s on before you start adding things, otherwise your ingredients might flash-freeze to the side and make the paddle stick. Oh, and store it in the freezer door, it’s less cold there so it makes for a better ice cream.
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