How to sub fresh tomatoes for canned?

With the tomato abundance at the market right now, is there a general rule of thumb on how to substitute fresh tomatoes for canned? How should I prepare the fresh tomatoes, if at all, and how can I measure everything accurately for similar results? Do canned tomatoes (like San Marzano) have a flavor that can't be easily replaced with fresh? I'm eyeing this recipe for eggplant parmesan: Thanks all!

  • Posted by: Angela
  • August 22, 2012


Cannizzo August 24, 2012
Pierino thank you for that tip I thought if it said San Marzano it was from San Marzano I looked at the brand I use and I'm glad to see that it is the real thing but I shop at a store here that is a cross between a mega store and an Italian gourmet shop again thank you
Kristen W. August 24, 2012
Pierino, thanks for the history lesson -- I find it fascinating! I wonder, then, if tomatoes are a New World product, how and when they made their way into Middle Eastern and South Asian cuisines (though I guess it's not that far of a leap from Spain to the Middle East, now that I think of it).
Angela August 23, 2012
what would I look for to find the "real thing"?
pierino August 23, 2012
Angela, look for "product of Italy" on the label. There are quite a few Italian brands that are available at retail here. One is "Bella Terra" but you don't have to seek that one out specifically. You are unlikely to see them at your local megamarket but they are actually not that hard to find depending on your demographic. Gourmet stores, Sur La Table, Whole Foods etc. The difference in flavor is really distinct. It's funny how a food product of the Americas has been refined in Italy and then shipped back over to us.
Cannizzo August 23, 2012
Pierino can you tell me the brand name ?
pierino August 23, 2012
Cannizzo, the company that packs the tomatoes is actually using "San Marzano" as its brand name/trademark. It's not illegal just misleading when you are looking for the real thing.
Angela August 23, 2012
Thanks everyone for the help and info!! :)

I blanched, peeled, chopped and weighed fresh tomatoes last night to use for a quick chili and it turned out great! We had some leftover tomato paste in our fridge so I threw that in as well for the depth of flavor (since it's kind of a stew we're likely to reheat a lot).

When we get eggplant at the market this weekend for the eggplant parm, I'll try the tomatoes with just the whole basil leaf. I'm sure the fresh tomato preparation will pair nicely with the eggplant roasting technique in the recipe!

Hooray Hotline!!
Kristen W. August 23, 2012
Pierino, did you just say that tomatoes weren't accepted as a food in Italy until the 1830s? If so, Interesting!
pierino August 23, 2012
Kristen W, more like the mid 18th Century. The short history of the tomato goes like this; it arrived in Spain with Colombus. At first it wasn't accepted as a food product because it's a member of the nightshade family. But from Spain it made its way to Italy. Napoli was part of the Kingdom of the Two Scilies---a Spanish Bourbon possession. It was in the 1830's that the industry took off because of the soil, thank you Mt. Vesuvio. The first tomato hit pizza somewhere around 1860.
Cannizzo August 22, 2012
No I don't agree on the tomato paste I'm from Naples not to far from San Marzano and in that region of Italy adding anything to a fresh tomato takes away from that fresh taste you are looking for unless it's a long cooking tomato sauce the only thing we would do is blanch them skin them for whole tomatoes for canned sauce wich we canned every year we would cook the tomatoes sliced skin on in a pot no water added get them soft and pass through a food mill and then add a fresh leaf of basil or two to the sauce in the jar then boil the whole jar to preserve if you notice when you buy San Marzano tomatoes or San Marzano tomato sauce that is always whole basil in it
pierino August 23, 2012
I'm with Cannizzo on the tomato paste thing. What makes San Marzano tomatoes special is that they've adapted spectacularly to the volcanic soil around Naples. Even though Tomatoes weren't accepted as food (a New World fruit) right away the tomato industry in Napoli began to thrive in the 1830's owing to the wonderful growing conditions. One thing to be wary of is that in the US there is a domestic label which uses "San Marzano" as its brand. The tomatoes are grown in Arizona. The can has a white label and even though the seeds may be San Marzano that makes no difference. The fruit itself is inferior.
bigpan August 22, 2012
Consider adding some tomato paste to boost the flavor.
chef O. August 22, 2012
I agree that you should substitute by weight- 1for 1

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pierino August 22, 2012
Go by weight. A large can of tomatoes weighs 28oz. Substitute an equivalent measure of fresh tomatoes. You will want to blanch and peel them first but that's pretty simple. It's great to have delicious canned tomatoes out of season, but right now go ahead with the fresh ones.
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