|MadSci Network: Agricultural Sciences|
Ice cream is not actually made with seaweed as an ingredient. What's inside the ice cream is a gum extracted from the seaweed, called carrageenan, named after the place in Ireland where the seaweed is collected. Gums, such as those used in sealing tape and candies, come from all types of plants. They are sugars bonded together in very long strands like a necklace. Since seaweed lives in the sea, the gum made from it loves water. This is why it is used in ice cream. The gum, even in small amounts, ties up the water in the ice cream, making it thick and smooth instead of thin and runny. It also keeps the water from forming ice when it sits in your freezer. If you look on the ice cream package label, you should see the name carrageenan. Only a half-teaspoon is used in the entire half gallon of ice cream.
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