Be Aware of Spoilage Signs in Canned Foods

Question: Many, many (like 8 of 10 cans of mushrooms and like- amounts of canned peppers) at one time or another have “hissed” when I have opened them. Even at $1.19 or $1.23 per can of mushrooms and 53 cents for chiles, out they go. Am I doing the right thing? These cans were not bulging or dented, and the tops were flat. I wondered about air pressure, but if I opened a can of soup it doesn’t hiss.

Answer: We contacted the Canned Food Information Council and received the following reply:

“I’m writing in response to your question of whether or not cans should ‘hiss’ when they’re opened. Some cans may ‘hiss’ because they are vacuum packed and the noise is a result of air pressure, which is perfectly normal. However, if a can ‘hisses’ loudly or spurts when opened, it may be an indication that the food is spoiled. Consumers should be aware of the warning signals of spoilage. If a can is rusty, if it leaks, if ends appear bulging or if food has an off-odor, it should be thrown away.”

Q: I have been growing tomatillos in my garden this summer and am interested in canning them for future use in salsas and other sauces. I was not able to find any information on tomatillos in any of the books on canning at the library. Is it possible to can them by following the same procedures that are used for canning tomatoes, or is it necessary to use a steam pressure canner? I would appreciate any information you have on this. Thank you.

A: None of the sources we checked recommend canning tomatillos by either the water bath or steam pressure method. However, according to Elizabeth Schneider, author of “Uncommon Fruits & Vegetables--A Commonsense Guide” (Harper & Row: 1986, $25): “Tomatillos freeze extremely well, once cooked. Husk, wash and stem them. Combine with water to barely cover; keep at under a simmer until softened, but not squishy. Cool in the liquid, then freeze in cooking liquid in 1-cup containers for handy sauce-making (use both fruit and liquid for this; do not drain).”

Q: When a recipe calls for meat or poultry to be put in a roaster and then baked in the oven, do they mean for it to be covered or uncovered? Most recipes do not specify which they mean.

A: If no directions are given to cover the meat or poultry, it should be cooked uncovered. The term roast is defined in “Sunset Easy Basics for Good Cooking” (Lane: 1982) as “to cook meat or poultry, uncovered, by dry heat (usually in an oven.)”

Q: Is it possible to locate a new or used copy of the book “Classic Sauces and Their Preparations” by Raymond Oliver (World Publishing)? Thank you for any assistance.

A: Marian L. Gore, Bookseller, specializes in out-of-print books on food and drink. Although she does not currently have a copy of the book you are seeking, she will keep your name on file in case one becomes available. Other inquiries and requests for her catalogue may be directed to Box 433, San Gabriel 91778-0433.