Olive oil. Drizzle it, toss it, spoon it over your fish. It enriches the flavour of your food and it's cholesterol free. That's why it's one of the hottest products in the market place today.

Canadian stores stock more than 100 brands of olive oil ranging in price from more than $40 a litre to less than $4 a litre.

But price-conscious shoppers who purchase low-priced olive oils have to be careful. Some products that look like bargains could be fake.

Joe Di Lecce, a food specialist with the Canadian Food Inspection Agency, says "we found oils that consisted mainly of vegetable oils other than olive oil," during inspections. "Some had sunflower oil, some had canola, some had pomace oil."

Joe Di Lecce

Di Lecce is the CFIA's olive oil specialist. Since 1997 he has being checking out olive oils to see if they are what they're advertised to be. Di Lecce has looked at 100 oils, and found that 20 per cent are fake.

And, he says, consumers can't tell the difference just by looking at a bottle in a store. "Most of the oils look pretty good. It's very difficult for a consumer to know if something's wrong."

Di Lecce has samples analyzed by the CFIA's lab in Ottawa, where they're subjected to a battery of tests that have revealed some oils were adulterated.

Stan Bacler

"Adulteration would be the addition of cheaper grades of olive oil to an expensive grade or addition of cheaper substitute oils to olive oil to extend and increase profits," says Stan Bacler, a food chemist with the CFIA.

In some cases, says Bacler, less than half the oil in the bottle was genuine olive oil.

According to Di Lecce, once the lab tests uncovered the adulterated oils, the CFIA laid charges against the companies linked to the products.

The Agency successfully prosecuted 11 wholesale and distribution companies which sell oil to retailers right across the country.

• Click here for a list of impure oils and the distributors who have been prosecuted.

Two more prosecutions are in the works, and there will likely be more. Stan Bacler says the profits to be made from selling fake oils are enough to make the fakers very inventive.

'It's a challenge to stay one step ahead of the people doing the fraud,' says Bacler

"It's a challenge to stay one step ahead of the people doing the fraud," says Bacler. "They know after a while which tests we do and what we can detect and while we are looking for these things they're already looking for new ways in which to either fool the testing we are doing or to find different ways which cannot be detected."

Those that have been detected have paid fines ranging from $7,000 to over $22,000, and Joe Di Lecce thinks that's been a serious deterrent.

"We believe it to have been fairly effective (as a deterrent)," he says. "We are continuing to monitor, we are continuing to sample. The industry is aware that we are there, that we are taking action that we are seizing product and prosecuting any company we find that has adulterated olive oil ... We've not discovered any further cases of adulteration."

Di Lecce thinks the fines have worked as a deterrent

Feel safer now? You shouldn't. The Canadian Food Inspection Agency hasn't turned up any more fakes, but Marketplace did when we did some investigative shopping of our own.

We purchased olive oil samples at stores in Toronto and took them to a private laboratory. We bought five low priced oils, including two brands sold by companies the CFIA had already successfully prosecuted.

Technicians analyzed the samples. Their findings were dramatic.

Of the five samples tested, two turned out to be clearly adulterated according to our lab's chief chemist.

Terra Mia and San Paulo are two oils we tested

The two fakes were brands distributed by companies the CFIA had prosecuted six months earlier. The Terra Mia and the San Paulo are two that we tested. They're still on the shelves.

The CFIA's Di Lecce says "it's possible that six months after the prosecution there were still some products remaining from their distribution."

But why weren't they pulled off store shelves?

"This product is in every single supermarket across the country," Di Lecce says. "It would be just too overwhelming to have a person go into every single store and find the product."

'Buy a brand that you recognize,' says Di Lecce

Di Lecce says that if the adulterated oils posed a health hazard the food inspection agency could order a recall, but simple fraud isn't a serious enough issue, so the fake oils stay.

Given that, what's Di Lecce's advice for consumers who want to buy bona fide olive oil?

"Buy a brand that you recognize, buy a brand that's been established, don't let price be your only guide, talk to people who have purchased the product before, and just [remember] 'buyer beware' ... and you should be okay."

Adulterated oils:

• Olivio (from Greece)
• Terra Mia extra virgin
• Ricetta Antica extra virgin
• San Paolo
• San Paolo extra virgin
• Andy's Pure Olive Oil
• Italico extra virgin

Distributors caught:

• Cher-Mor Foods International
• AMT Fine Foods
• Siena Foods Ltd.
• Lonath International
• Bella International Food Brokers
• Les Aliments MIA Food Distributing
• D & G Foods
• Deluca Brothers International
• Kalamata Foods
• Mario Sardo Sales Inc.