When an outbreak of food illness occurs, the procedure for limiting damage relies on food safety testing and finding the source of the pathogen. But what would happen if the offending product were tracked down, only to discover that it was made with ingredients from, say, 60 different countries?

Such was the case when U.K. food safety inspectors took a closer look at a packaged pizza. The mongrel pizza wasn’t part of a food illness investigation, but came to the attention of the National Audit Office (NAO) during testing prompted by the now-infamous horse meat scandal.

The pizza in question was labeled, “Country of origin: Ireland.”

Simple enough, or so it would seem, but when they looked further, they discovered that the pizza was actually made with 35 ingredients from 60 countries.

What if that pizza had been involved in an illness outbreak? Tracking, verifying and recalling the ingredients would have been nearly impossible.

The pizza and its international hodgepodge of 35 ingredients was recently used as an example in a report by the NAO to highlight how difficult it has become to determine what exactly is in our food, much in thanks to circuitous, global supply chains.

How long was the pizza’s supply chain? Seemingly long enough to wrap around the planet:

Dough: France, U.K., Poland, USA

Yeast: U.K., Ireland, Germany

Salt: U.K., France, China

Sugar: Brazil, Indonesia, Jamaica, U.K.

Herbs: Greece, Italy, Spain, Kenya, Uganda, Tanzania, Morocco

Tomato paste: Italy, France, Netherlands

Cheese: Switzerland, Ireland, France, Italy, Spain, U.K., Netherlands

Chicken: Brazil, Ireland, U.K., Netherlands, Germany

Anchovies: Peru, Argentina, Italy, Falkland Islands, Spain, Iceland, Denmark

Pepperoni: Poland, Italy, Ireland, U.K., Denmark, USA

Vegetables: From a host of Mediterranean countries

Olive oil: Italy, Greece, Spain

Chili peppers: Africa, Asia, South America

In the report, the NAO warned that “food fraud was rife.” And what a startling example the simple pizza turned out to be, labeled as a product of Ireland while in reality a fraudulently labeled product from Ireland … and 59 other countries as well.

And it’s not just the U.K. where food fraud is frequent. In the United States, the Food Fraud Database maintained by the nonprofit U.S. Pharmacopeial Convention lists so many commonly consumed products that have undergone "deliberate substitution, addition, tampering or misrepresentation of food, food ingredients or food packaging, or false or misleading statements made about a product for economic gain," it’s a wonder any of us still want to eat packaged food.

With expanding trade agreements, notably the World Trade Organization, there is more cheap food surging into the United States than ever. This ever-growing global supply chain of minor ingredients — like a pizza cobbled together from ingredients collected from 60 different countries — makes it exceedingly difficult to track foodborne illness and monitor production practices of suppliers, making food safety testing all the more important.

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