This is the time of year when tomatoes are ripening on the vine in both the U.S. and Italy. Even if you don't grow your own tomatoes, this can be also the time to make your own Italian style passata di pomodoro--a basic tomato sauce that has all the skins and seeds removed, with all the flavor left behind.
Here in the states, the closest canned product is called "tomato puree". Many families in Italy make the processing and canning of passata a yearly event--a family event--making enough jars of passata to last the entire year, often enough for extended famiglia. If you're not growing enough of your own paste style tomatoes, you can always buy a bushel or two or three from your local farm stand. Some Italian families will process up to 500 pounds of passata each year!
Think of passata as a basic tomato sauce which you can use in all sorts of recipes, or even as a base to make other tomato-based sauces, such as Puttanesca, Amatriciana, Bolognese (ragu), Vodka sauce, sugo ("Sunday Gravy") or for pizza sauce. The word "passata" (passed, screened, smashed) refers to the processing with a special food mill that removes the seeds, pulp and skins, leaving only the tomato sauce behind. Other family recipes might just use a common food processor or blender, but this can't really give you a genuine passata.
The cleaned, ripe tomatoes are cut up, boiled and processed to remove the skins and pulp, and finally canned in a traditional manner using a hot water bath and canning jars. Some family recipes might also add other spices or flavorings such as garlic as they boil the tomatoes, but since passata is a base to make a wide variety of sauces, you might want to add them at the time of cooking the final sauce. It is traditional, however, to add one large basil leave into each jar canned.
The Method of Making Passata
Although you can make a passata in very small quantities, we will look at how to make a large volume for the purposes of canning and storage. We would love to promote this time honored, annual ritual here in the United States. Wouldn't it be better to have a yearly stock of your own tomato passata rather than buy supermarket sauces filled with chemical preservatives and other additives?
What Type of Tomato is Best?
In Italy, the best for this is San Marzano tomatoes (used in the best imported canned tomatoes), which have DOP protection and are only grown in the area of Naples surrounding Mount Vesuvius. Of course, many varieties are grown in the U.S. calling themselves "San Marzano", but they are only a similar variety. (You can't match San Marzano tomatoes because of their uniqueness of being grown in volcanic soils.)
In reality, any good-tasting, full-bodied paste type tomato will work well. The tomato you select should have sweetness, depth of flavor, but also a touch of acidity--which benefits long preservation. Most paste tomatoes are thick fleshed and have a similar shape to San Marzano--that is, an elongated plum shape. You can also use larger cherry tomatoes or horn-pepper shaped varieties. Again, if it has a great taste, it will make a great passata. Leave the larger, beefsteak varieties for slicing and eating fresh.
If you want to grow your own heirloom canning tomatoes from seed, we can highly recommend Striped Roma (horn shaped, sweet), Jersey Devil (horn shaped, very meaty), Debarao (plum shaped, juicy) and Martino's Roma (classic plum tomato). If you want to plant enough for lots of passata, plan on planting a minimum of 10 plants of one single variety that you earmark for canning.
How Many Tomatoes?
This really depends on how ambitious you are. if you use lots of tomato sauce in your recipes each year, then start with more tomatoes. You will also need more canning jars, lids and other varied supplies and tools. Having a very large pot or cauldron to boil the tomatoes helps prevent tedious, repeated boiling/canning sessions. I highly recommend doing it the way most Italians do it--using a tomato processing mill. I also love the way Italians use a very large pot to boil their jars and to do the final canning process--they use kitchen towels to layer in the glass jars to protect them from rattling around against each other.
Here are some guidelines:
3 pounds of tomatoes to make 1 quart of passata.
21 pounds of tomatoes will make 7 quarts of passata.
One bushel of tomatoes (about 53 lbs per bushel) will give you 15-18 quarts of passata.
You will also be using sea salt and placing basil leaves into each jar.
Things You will Need
(For a large volume...)
You can use a standard hand-cranked food mill or a manual tomato milling machine to process the tomatoes, but if you're doing a large volume, you should consider investing in a powered tomato mill. The more power the unit has, the faster your processing will go. You might need to set up your milling machine on a low table, with bowl on the table to capture the pulp and a large container on the floor to capture the passata.
What About Canning Whole Tomatoes?
In Italy, whole canned tomatoes are called pelati, referring to the process of peeling the skins off before canning. In the area of Naples, many families invest in crates of locally grown San Marzano tomatoes, but any pear/plum shaped past tomato will do fine.
Before caning whole tomatoes, the best way to prevent spoilage is to remove the skins. Canning peeled tomatoes also affords more options for use in recipes that might call for crushed tomatoes. Skinned, whole tomatoes are easy to crush by squeeze by hand or pulsing in a food processor.
Don't forget to label your Passata and Pelati with the month and year. (Order oval Avery labels HERE on Amazon). Store them in a cool, dark place. They will last for as long as three years.
Read this article carefully, watch the videos below and by all means, work safely! Make this a yearly event for your extended famiglia. I've read about families who take gather large teams together to process as much as 500 pounds of tomatoes! I would suggest starting small until you get used to the process. You can also make small volumes of passata or pelati right in your kitchen with a large stock pot, colander and tools you have lying around. And whether you use a manual tomato mill or powered, I'm sure you'll be successful and enjoy a fully packed cantina (pantry) all season long.
--Jerry Finzi, GVI
If you are new to canning, you can study the principles of safe canning HERE.
Useful Processing Tools on AMAZON...
The video below is one of the best I have found covering many aspects of making Passata and Pelati. There are some titles in English,
but it might also help to click the gear icon on YouTube
to turn on Closed Captions and Auto-Translate to select English...