This is a very shocking story. It is completely unacceptable. And people will be very angry to find out that they have been eating horse when they thought that they had been eating beef. - British Prime Minister David Cameron

British Prime Minister David Cameron isn't the only one shocked to find out what's really in his frozen dinner.

Un-labeled horse meat has turned up all over Europe in frozen supermarket-sold meals like lasagnas and shepherd's pies, in pasta sauce and in school lunches. Latest reports say it's turned up as far away as Hong Kong. Millions of products have been pulled off store shelves and people's faith in their food supply has been badly shaken.

According to John Spink, the increasingly global nature of our food supply chain means that it's getting more difficult to be absolutely sure of what we're eating.

John Spink is the Associate Director of the Anti-Counterfeiting and Product Protection Program at the School for Criminal Justice at Michigan State University. Before that, he spent 15 years in the corporate sector, working on food fraud and other fraud issues. John Spink was in East Lansing, Michigan.

In addition to the horse dressed up as beef, a new study out yesterday suggests seafood fraud is even more common than we might have thought.

Kimberly Warner is a senior scientist with the group Oceana, co-author of the study. They had the University of Guelph do DNA testing of fish samples from the U.S. We aired a clip with some of what they found.

Nicholas Low has been working on a way to detect food fraud for more than a decade. He's a professor of food chemistry at the University of Saskatchewan. The methods he has developed for verifying food authenticity are already being used by governments and corporations around the world. His latest research involves a tagging system which he says could trace food from "farm to fork." Nicholas Low is currently overseas on sabbatical in London.

Yesterday afternoon we asked Health Canada to comment on measures they are taking to crack down on food fraud. We are waiting for a response. And we'll let you know when we get it

This segment was produced by The Current's Dawna Dingwall, Heather Barrett and Sarah Buck.

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