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Ice Cream Made Easy!
Edible Fibre Optics
Make your own ice cream at home!!
It tastes sweet, but you need
salt to make it...Curious? Let's find out why....
| WHAT YOU NEED:
1/2 cup cream 1/2 cup milk 1/4 cup sugar 1/4 teaspoon vanilla 1/2 cup kosher salt or rock salt 2 1/2 cups crushed ice quart- and gallon-size zip seal freezer bags berries, nuts, chocolate chips or other ice cream toppings |
1. Get quart and gallon size zip-seal freezer bags, 1/2 cup cream, 1/2 cup milk,
1/4 cup sugar, 1/4 teaspoon vanilla,1/2 cup kosher salt or rock salt and
2 1/2 cups crushed ice.
2. Pour the cream, milk, sugar and vanilla into a quart-size freezer bag and seal it tightly. (It's very important to make sure that it’s completely sealed.) Knead or shake the bag to mix the ingredients. 3. Drop the quart-size bag into a gallon-size freezer bag, along with the crushed ice and the salt. Seal the outer bag securely, too. 4. Shake the pair of bags vigorously for roughly 10 or 15 minutes. You’ll see the ice in the outer bag melting, but the resulting salt water will still be very cold. 5. Pull the small bag out of the big bag, rinse it off, scoop out the ice cream and enjoy! Try it with berries, nuts, chocolate chips or a cherry. |
The shaking is what gave your dessert the creamy texture you expect. If you had just tossed the inner bag into your freezer, the ingredients would have separated as they froze, and you would have gotten a chunk of ice crystals, fat globules and sugar solids. The shaking also helped get air into the mixture, which made it light and smooth.
But you still needed to get your ingredients colder
than about 27 degrees Fahrenheit, the temperature at which the mixture
freezes. Ice cubes would have been cold enough to do it, but if you had
just put ice in the outer bag, warm air pockets between the ice chunks
would have kept them from cooling the inner bag efficiently. A liquid can
do the job better, because it can surround the inner bag, touching it all
over. But if you had just let the ice melt, the resulting ice water would
have been at 32 degrees F—too warm to freeze the cream mixture.
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Adding salt helped create a liquid colder than 32 degrees F. The sodium and chlorine atoms in salt interfere with the bonds that hold water molecules together in an ice crystal. That can make some of the water molecules detach from one another, forming a liquid that’s still very cold. (That’s why in the cold weathered countries, they could melt the |
People will do a lot for a frozen dessert. The Roman Emperor Nero, for example, is said to have sent slaves into the mountains for snow to mix with nectar, fruit and honey. And George Washington one summer reportedly spent $200 (about $2,000 in today’s dollars) on ice cream. But today you don’t need slaves or a lot of money to have fresh ice cream. In fact, you don’t even need the freezer section of your local grocery store. If you know a little science, you can make your own frozen treat right at home with ingredients you might already have on hand. Try it. You may be surprised at the results—and at how hard it is to save any dessert for after dinner.
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