Types of Canned Tomatoes
Are you tired of making tomato sauce with winter tomatoes that taste like cardboard? You should be. Even in the middle of summer, finding a good tomato is like finding a needle in a haystack unless you grow your own, which leaves us with canned tomatoes. But how do you choose from the five different kinds at the store?
Whole Peeled Tomatoes are whole tomatoes that are peeled (either by steaming or by being treated with lye), then packed in tomato juice or tomato purée. Those packed in juice are less processed and therefore more versatile (tomatoes packed in purée will always have a "cooked" flavor, even if you use them straight out of the can). Sometimes calcium chloride, a firming agent, will be added to help prevent them from turning mushy, but I prefer tomatoes packed without it. You'll also see them packed with basil leaves.
Diced Tomatoes are whole peeled tomatoes that have been machine-diced, then packed in juice or purée. The main difference here is that, with a greater exposed surface area, the calcium chloride can make the tomatoes too firm: they don't break down properly when cooking. I don't use them.
Crushed Tomatoes can vary wildly from brand to brand. There are actually no controls on the labeling of crushed tomatoes, so one brand's "crushed" may be a chunky mash, while another's is a nearly smooth purée. Because of this, it's generally better to avoid crushed products, opting instead to crush your own whole tomatoes.
Tomato Purée is a cooked and strained tomato product. It makes a good shortcut for quick-cooking sauces, but your sauce will lack the complexity you get from slowly reducing less-processed tomatoes. Leave the purée on the shelf.
Tomato Paste is concentrated tomato juice. Fresh tomatoes are cooked, then the larger solids are strained out and the resulting juice is slowly cooked down to a moisture content of 76 percent or less. Tomato paste is great for adding a strong umami backbone to stews and braises, as well as for thickening them slightly.
So diced tomatoes are too firm, crushed tomatoes are too inconsistent, and tomato purée is too cooked— which is why in my pantry, you'll only see whole peeled tomatoes packed in juice (I prefer Muir Glen and Cento brands) and tomato paste.
Excerpted from The Food Lab: Better Home Cooking Through Science.
