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Glycoproteins, Xylomannan, And Bug Protein In Your Ice Cream

Have you ever wondered how ice cream can stay very cold but not form ice crystals? Well, there is an ingredient called ice-structuring protein that is added. It sounds similar to anti-freeze but it's not the same as what you would put in a car.

Anti-Freeze?



Anti-freeze that you put in a car is called ethylene glycol and it's poisonous. This anti freeze protein comes from animals like fish, spiders, and insects.

Tasty Right?



Well, they're not adding fish and bugs to the ice cream, only protein.

You see, in the 1950s scientists wondered why some Arctic fish could survive in waters cold enough to freeze their blood.

Glycoproteins



It wasn't until the late 1960s that glycoproteins that inhibited freezing were discovered. These proteins attach to particular surfaces on an ice crystal and can prevent it from growing and rupturing an animal's cells.

Since that time, five different types of anti freeze proteins have been found in flounders, smelt, herring, and other fish.

Insects too?



Yes, research in the last ten years has found dozens of insects and spiders with anti freeze proteins. Some insects are freeze tolerant down to 40 to 94 degrees Fahrenheit.

Even more amazing is that scientists have found an Alaskan beetle that can survive temperatures down to 104 degrees Fahrenheit.

Xylomannan



Instead of glycoproteins, the beetle uses another kind of molecule made of sugar and fatty acids to keep from freezing called xylomannan.

Scientists think it works in a different way than the glycoprotein, but more research is needed to find out exactly what it does.

So, am I going to be eating beetles?



Ha. Ha. Not any time soon.

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