Elaine Corn: When Charles Shoemaker stands in an olive grove near
his lab, he sees more than the makings for salad
Charles Shoemaker: As a chemist, I can imagine all the
polyphenolic compounds and Vitamin E, and all the wonderful flavor
and healthful aspects of the olive, and just waiting to get our
hands on that fruit to extract that wonderful
EC: To be extra-virgin, olive oil can't be rancid, adulterated
with cheap refined olive oil or cut with lesser oils. That's where
Shoemaker and his olive oil forensics come in.
Shoemaker: We have our own CSI: Olive Oil lab,
EC: Shoemaker is inside the 3rd floor lab in the
Robert Mondavi Institute for Food and Wine Science. Windows
overlook the campus's 2,000 olive trees. The room has an atmosphere
Shoemaker: It's become a very sophisticated
practice, the adulteration of olive oil throughout the
EC: The lab's décor? Cement bunker with beakers and test tubes
and chemistry toys.
Shoemaker: We have lots of magnetic stirring bars
because there's a lot of mixing that goes on in a chemistry lab.
These are pipettes to measure very exacting volumes. We use as
small as milligrams of oil that go into these expensive
EC: This lab's equipment uncovers defects, degradation and
dilution in olive oil.
Shoemaker: We do spectroscopic studies
looking for oxidation.
EC: That means the oil's old or rancid. To be fair, any oil
could suffer indignities during shipping, like a slow boat or a hot
warehouse. But, there are OTHER tests. Shoemaker analyzes free
Shoemaker: ... to make sure the oil is all from
olive, and not from soybean, sunflower or other types of
EC: For the study, Davis did some of the tests. A lab in
Australia did others. In all, 104 bottles of olive oil from Los
Angeles, Sacramento and San Francisco got a tested. Many big name
imports did not fare well. The study came immediately under fire.
The researchers had used standard tests known to the olive oil
world, but added a few new tests.
Bob Bauer: It's
irresponsible to create the misperception that they've done based
on unrecognized tests.
EC: Bob Bauer of the North American Olive Oil Association,
which represents importers, disputes the Davis study.
Bauer: These results directly contradict our 20
years of more extensive sampling than what those results
EC: Shoemaker says the Davis lab goes beyond international
Shoemaker: The level of testing here is a bit more
EC: One of the new tests is a pricey gizmo that sounds like
this. Shoemaker revs up a vacuum. It removes solvents and isolates
chlorophyll to check if tasteless refined olive oil is in the
Shoemaker: It takes about 25 minutes per sample
for just this one step.
EC: The number one reason people buy olive oil is for health.
Patricia Darragh is with the California Olive Oil Council, which
helped fund the Davis study along with two California olive oil
producers. Darragh says knowing which olive oils deserve the
extra-virgin label is important for consumers.
Darragh: It's not only that people are spending
good money for a fraudulently labeled product, but they're not
getting the health benefits that many people want when they think
they're purchasing extra-virgin.
EC: The new olive oil study may be preliminary, but it names
names. Bertolli, Mezzetta, Mazola and Pompeian oils labeled
extra-virgin, were not. Shoemaker says his lab has only
Shoemaker: There's some fairly sophisticated
people. They seem to adapt and come up with new innovative way to
find their way around the new test. So, it's going to be a long
business, I think here.
EC: The goal of the lab is to make sure that the olive oil you
buy is what the label says it is. Elaine Corn Capital Public Radio