Canned Whole Peeled Tomatoes

One US cup of canned whole peeled tomatoes weighs 240 grams (8.5 ounces). Going the other way, 100 grams is about 0.42 cups.

Also called whole peeled tomatoes, canned whole tomatoes, whole tomatoes, peeled plum tomatoes, San Marzano tomatoes, pelati.

Tomato paste, puree, sauces, canned tomatoes, juice and ketchup compared: cup weights side by side, the source behind each, and why they differ.

Canned whole peeled tomatoes weigh 240 g per US cup (8.5 oz) with their juice, a density of 1.014 g/mL. USDA's two canned-tomato records give 240 g, and Hunt's, Contadina, Red Gold and Muir Glen label half a cup at 120-122 g, which is 240-244 g per cup, within 2%.

Whole peeled tomatoes are ripe tomatoes, usually plum or Roma types, scalded so the skins slip off, then packed whole in tomato juice or a light puree. They are the base of slow-cooked sauces and the can that pizza and pasta recipes most often ask for, including the San Marzano style. The US standard for canned tomatoes (21 CFR 155.190) lets them be packed in juice or in puree; USDA puts the juice-packed can at 94.8% water.

USDA SR Legacy "Tomatoes, red, ripe, canned, packed in tomato juice" (FDC 170051) lists 1 cup at 240 g and 1 tablespoon at 15 g, and the no-salt-added record (FDC 170138) gives the same 240 g cup. USDA does not split whole from diced in these records; they describe juice-packed canned tomatoes generally. The brands label the whole-peeled can itself: Hunt's, Contadina and Red Gold 121 g per half cup, Muir Glen's regular and San Marzano-style cans 122 g and 120 g. O Organics, Kroger, H-E-B, Tuttorosso and Bianco DiNapoli also print 120-121 g. King Arthur's chart has no row for canned tomatoes.

The physical check works out to the gram. Tomatoes and their juice are both mostly water carrying a few percent of sugars, acids, pectin and fibre, all denser than water. At USDA's 94.8% water and 3.5% carbohydrate, the mixture should be about 1.8% denser than water, which is about 241 g per cup. USDA measures 240 and the labels 240-244. Whole tomatoes in a cup leave pockets, but the juice fills them, so there is no air to account for, unlike a cup of shredded cheese or flour.

One label sits outside the rest. Cento's certified San Marzano cans give half a cup at 115 g, 230 g per cup. That would make tomatoes in juice lighter than water, which they cannot be, so that figure is not used here; it looks like a rounded serving weight rather than a measured half cup.

Practical guidance: a 28-oz can holds 794 g, about 3 1/3 cups of tomatoes and juice; a 14.5-oz can 411 g, about 1 3/4 cups. Recipes that call for "1 cup whole tomatoes, crushed by hand" mean 240 g of tomatoes with their juice. Draining removes most of the juice and the figure no longer applies, so weigh drained tomatoes. Whole, diced and crushed tomatoes in juice all weigh about the same per cup; crushed and diced tomatoes packed in puree run heavier.

The tomato products comparison page shows whole peeled tomatoes beside crushed and diced tomatoes, puree, sauce, paste, juice, marinara and ketchup.