What Do Propellers and Beer Have in Common?

Cavitation can speed up the aging process of alcohol in barrels. (Photo: Shaiith/Shutterstock)

The past decade has seen the rise of molecular gastronomy, the combination of culinary arts with sciences like chemistry, physics and, now, marine biology.

What does marine biology have to do with cooking? When a pistol shrimp snaps its claws, it does it with such speed that cavitation bubbles hit its prey with a force that stuns. A cavitation bubble is a tiny hole that's ripped into fluid when the fluid is moved violently. When the hole collapses, it sends a shockwave that breaks through the liquid that it's in.

It happens in the kitchen, too. When a blender creates cavitation bubbles with its violent motion, the collapse of bubbles creates a smooth puree or a rich emulsion of the foods in the blender, according to ChefSteps.

Humans have been aware of cavitation only since 1895, when we noticed the tiny, forceful, ripping, shock-wave inducing bubbles on torpedo boat propellers, according to NPR. And while kitchen blenders have been creating cavitation bubbles for a long time, the culinary world has been working with cavitation bubbles in other areas of food and beverage for only a few years.

Culinary uses for cavitation

white eggs carton
Cavitation can pasteurize eggs while minimally damaging their proteins. (Photo: FotAle/Shutterstock)

Egg pasteurization: A rotator with holes in it creates cavitation bubbles that are heated from within. The pasteurization machine's surface is cooler than the hot bubbles. The bubbles pass over the eggs, pasteurizing them, but they don't harden. By controlling the intensity of the cavitation, the proteins in the eggs are minimally damaged.

Dairy: Cavitation can aerate dairy and make products like yogurt seem fluffier.

Brewing beer: Cavitation converts starch in barley into breakable sugars without having to germinate the barley first. This saves time. Brewers have found they can use the same process to extract more flavor from ingredients they infuse into beers such as coffee and fruits.

Aging alcoholic beverages: Cavitation accelerates barrel aging by extracting flavor from charred wood chips, quickening the process for whiskey, wine and other alcoholic beverages. According to Makezine, using a cream whipper to create nitrogen cavitation can create instant Limoncello or even marinated meats.

Food safety: Cavitation "catalyzes sought-after reactions" when blending food and neutralizes many "spoiling and harmful microbes."

There are cavitation procedures that are used on humans, too. It's in the process that successfully breaks up kidney stones with ultrasonic waves. It's also being used in ultrasonic fat reduction, also known as Lipo Cavitation, that claims to damage fat cell membranes, breaking them up and creating a slimmer you. It can take as many as 20 expensive sessions to see results, if there are any.