Most supermarkets contain aisle after aisle of shelf-stable canned foods, ranging from simple fruits and vegetables to fully prepared heat-and-eat meals. Those uniform rows carry the unspoken message that there's a substantial industry making the cans and manufacturing them to universally accepted sizes and shapes. The largest of these is the #10 can, a staple in restaurants and other large-volume kitchens. Cans this size can offer significant savings, but it's important to understand how much they hold before you start buying them.
If you're planning to fill your cellar or pantry with #10 cans for reasons of frugality or emergency preparedness, it's important first to know their physical size. The Can Manufacturer's Institute provides that information on its website, though the three-digit numbers used to express can sizes are somewhat odd to outsiders. The first digit is a number of inches, and the remaining two digits count sixteenths of an inch. The dimensions of a #10 can are listed as 603 X 700, or 6 3/16 inches in diameter by 7 inches high. Plan your shelving with those dimensions in mind, and leave enough additional room for your fingers.
Weight Of the Cans
Cans are a superlatively durable food-storage medium, but they're admittedly heavy. That's especially so for #10 cans, given their size. The weight of a can varies sharply, depending on its contents, but 6 1/2 to 7 1/2 pounds is a good average. A can of relatively small fruit in syrup, such as cherries or fruit cocktail, typically falls at the lighter end of that scale. Heavier and denser foods, such as pumpkin puree, come in at the top of the scale. If you're building shelves for your cans, be sure they're sturdy enough to bear the weight. If you're converting recipes to or from a given weight of fresh fruit or vegetables, assume an average of 6 to 7 pounds.
Volume Of the Cans
The other useful measure of a #10 can's size is its volume. Again, this can vary with the contents of the can. Dry fillings such as pumpkin puree or dry-packed fruit -- without syrup or water -- usually fill a can completely. Fruit packed in syrup or tomatoes in their own juice usually leave a small air space in the can, so you're less likely to make a mess when you open it. Accordingly, the contents of a #10 can will vary from 12 to 13 cups. If you're scaling down a commercial recipe, a few seconds of math will provide the correct quantity. It will also tell you how many smaller containers you'll need to hold the remainder of the can's contents.
The life expectancy of canned goods is almost indefinite, from the food safety perspective, as long as they're stored carefully. They should be in a dry, well-ventilated area, protected from spills, dents and substantial changes in temperature. If the cans are badly rusted or sharply dented, especially at a seam, their seals might be broken and the contents unusable. Once a can is opened, its contents require refrigeration. You can refrigerate non-acidic foods in the opened can for a few days, if they're well covered, but it's best to divide the remainder immediately between food-safe storage containers or freezer bags. Your storage time will vary, depending on the food and how it was processed.