5 Things You Might Not Know About San Marzano Tomatoes

Let's get philosophical for a minute. If the crust of a pizza is its backbone, the cheese and toppings its face, then the sauce is its lifeblood. Too often overlooked, the right sauce is key to a great pie. It should be tangy and just a little sweet. Ask any pizzaiolo worth his salt and he'll tell you: it should be made with San Marzano tomatoes.

But why?

Is it mere geography, San Marzano sul Sarno being not too far from Naples, the world's pizza mecca? Or, is it more than that? Well, for starters, this variety of plum tomato grows in the rich volcanic soil of the Sarno River valley, near Mount Vesuvius, resulting in a sweet flesh with low acidity. Its thick skin makes it easy to peel off. Plus, it's meatier than Romas and other plums, and has fewer seeds: all good things for making sauce.

There are probably plenty more reasons that San Marzano is the tomato of choice for pizza makers. But, some things you might have heard about these world-famous tomatoes simply aren't true. So to help keep you on the right path, we're setting the record straight about San Marzanos.

1. No, They Don't Grow In Brooklyn

Like French Champagne, San Marzano tomatoes are grown under strict rules designed to protect and promote regional agricultural products. In Italy, D.O.P. or Denominazione di Origine Protetta rules ensure that only growers within a defined area adhering to specific farming and canning methods can sell tomatoes labeled San Marzano. So, while you can grow the San Marzano variety in your backyard, they won't taste the same as the real McCoy. And you won't be able to stamp them as D.O.P. San Marzanos to sell at your local farmer's market, unless you're cool with breaking Italian law.

2. Yes, Some San Marzanos Are Fakes

Official D.O.P. San Marzano tomatoes are only sold in cans, peeled whole or cut in half. If your tomatoes come in a jar or are pureed, chopped, diced or even organic, they aren't the real thing. To make sure you're getting bona fide San Marzanos, look for the Pomodoro San Marzano dell'Agro Sarnese Nocerino D.O.P. label. Other brands might be of the San Marzano variety, but they aren't grown in the Sarno valley or don't meet D.O.P. criteria for some other reason.

3. Yes, You Can Make Neapolitan Pizza Without Them

Italians are serious about their pizza. Neapolitans even have an official body that governs how pizza must be made before it can be called verace pizza napoletana or "real Neapolitan pizza." While San Marzanos are the preferred tomato for Neapolitan pies, they aren't the only ones allowed. Corbarino tomatoes, from the town of Corbara, and piennolo tomatoes, also from around Mount Vesuvius, are permitted. GMO tomatoes are strictly forbidden.

Related: 4 Things You Probably Didn't Know About Neapolitan Pizza

4. No, San Marzanos Can't Kill You

OK, so maybe this one was debunked a long time ago. When tomatoes were first brought to Europe from the Andes, they were thought to be poisonous. That's likely because of the plant's similarity to the deadly nightshade, or belladonna. For a while, the fruits served merely an ornamental purpose in the Old World. Gradually, tomatoes went from a purported poison to a supposed aphrodisiac (in France) to simply good eats. It's quite a role reversal for a food that, according to science, actually helps to prevent deadly disease, not cause it.

5. No, San Marzanos Don't Come From Royalty

Another myth holds that the first San Marzano seeds were a gift from the Viceroyalty of Peru to the King of Naples in 1770. It's a romantic notion, but probably untrue considering that the plant was still widely feared in Europe at the time. By the way, the first tomatoes in Europe were yellow. The Italian word for tomato, pomodoro, comes from its nickname, pomo d'oro or "golden apple."

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