Ultrasonic French Fries
french fry? You ain’t tasted nothin’ yet! Research chefs have inveted
a new way of cooking fries that supposedly made them taste so much better.
The secret? A little ultrasonic wave:
Maxime Bilet, Johnny Zhu and the other research chefs (including
Young) at our culinary lab in Bellevue, Wash., explored a variety
of techniques for doing better still. The winning combination is simple
in its ingredients but quite fancy in its execution. The potato batons
are vacuum-sealed with 2 percent salt brine in bags to keep them intact
during boiling. They are then bombarded with intense sound waves from
the same device that dentists and jewelers use. A lengthy ultrasound
treatment at 40 kilohertz causes the surface of each fry to crack and
blister with myriad tiny bubbles and fissures.
The cook next vacuum-dries the pretreated potato sticks to adjust
the water content of the exterior and then briefly blanches them in
oil at 340 degrees Fahrenheit to tighten their network of interlaced
starch molecules. After cooling comes the final step: a quick plunge
into hot oil at 375 degrees F. Water flashes to steam inside each minuscule
bubble on the surface of the fries, expanding in volume by a factor
of more than 1,000 and forcing the bubbles to puff up. In just a few
minutes of deep frying, the french fries take on an almost furry appearance.