Surveying the Swiss: The eyes have it

Food scientist Moshe Rosenberg of the University of California, Davis has found that magnetic resonance imaging, or MRI, can help determine the health of a wheel of cheese.

MRI of Swiss cheese reveals defective wheel. Rosenberg/U.C. Davis

The size and distribution of holes, or eyes, in Swiss cheese contribute to its commercial value, says Rosenberg. Other cheeses, such as cheddar, should be free of eyes.

To evaluate the holes, which deliberately added gas-producing bacteria create, cheese makers currently bore or slice into a few cheese wheels from a larger batch. Since most wheels aren’t directly tested, quality becomes a game of chance, Rosenberg says. Even worse, if the eyes are unevenly distributed, a borehole might not accurately represent an entire wheel.

Rosenberg found that MRI could reveal the size and location of holes no matter how unevenly distributed or defective they were.

Allowing cheese to take up shelf space while aging is expensive, Rosenberg says. A diagnostic tool such as MRI could test for defects along a conveyor belt and help cheese makers reserve space for high-quality cheese.