Martha Stewart: Tips for those of the cloth (or sponge)

Dear Martha: Which is safer: a dishcloth or a sponge? And how do I prevent either from smelling?

A: It's not so much the tool that's the culprit in spreading germs in a kitchen - it's how you wield it. Dishcloths and sponges are equal-opportunity breeding grounds for bacteria, which thrive in the presence of food particles and in warm, moist environments. Millions of food-borne pathogens may be living in that one little cloth or sponge and can be spread easily from cutting board to countertop to other areas of the kitchen. Sponges can harbor more bacteria than dishcloths because they're thicker, dry more slowly and have lots of holes that can trap small food particles.

Whether you use a cloth or a sponge, rinse it thoroughly under hot running water after each use and wring it well. Store it so that it dries quickly and remains dry. Don't fold a cloth or leave a sponge in the sink. Consider using paper towels to wipe up meat or eggs.

Bacteria are to blame for the smell, so when you kill them, you automatically ward off any odors. You can destroy up to 99 percent of the germs on a cellulose sponge by microwaving it, soaking wet on a plate, for one minute on high or running it through the dishwasher on the hottest setting. This should be done daily or after you've been cooking with meat or eggs. Always wash dishcloths in hot water. Change dishcloths at least once a week, and replace sponges approximately every two weeks or as soon as they begin to fall apart.

Dear Martha: I've come across a lot of recipes that call for heavy cream or whipping cream. Is it possible to substitute one for the other?

A: Generally, one cream can be substituted for the other, although they are not the same thing. The difference is the amount of fat in each. Heavy cream has about 36 percent milk fat; whipping cream has about 30 percent. If you want really thick whipped cream, go for heavy cream. Whipping cream, which is a little lighter, can be used in eggnogs and to enrich soups and other savory dishes.

In addition to heavy cream and whipping cream, there is also light cream, which is usually 20 percent milk fat, and half-and-half, which is typically 12 percent. But both of these are too light to whip and should not be substituted for either heavy or whipping cream.

Dear Martha: How should I clean bookbindings?

A: The bindings on cloth- and leather-bound books can be quite fragile, so use the least aggressive nonabrasive cleaning method possible. First, wipe the book's surface with a microfiber cloth. For fabric-bound books, avoid liquid treatments, which may stain the exterior or seep through to the pages. Instead, use a white vinyl eraser, available at art-supply stores. Lightly roll the eraser over the cover to lift stray particles, or rub the binding to remove stubborn marks.

For leather-bound volumes, try a wax-based product, such as Triple Crown leather formula or JHS Leather Dressing. (Do not use on covers that are damaged or have a red, powdery surface, which indicates a type of deterioration known as red rot.) Apply with a lint-free cloth, avoiding gold tooling. Let the wax dry, and then buff the cover.

Bear in mind that these conditioners alter leather and may attract dust. An excellent way to preserve books is to use a vacuum cleaner. Set it to the lowest suction level, connect a dusting attachment and use a high-efficiency particulate air filter.

Dear Martha: Should I roast the chicken carcass before using it to make a stock?

A: It depends on whether you want a brown stock or a lighter one. For a darker, more richly flavored stock, first brown the chicken bones with an onion, a little bit of garlic, some carrots and celery. Then cover with water, and simmer. If you want a light-colored stock, don't brown the bones. This will result in a lighter flavor, appropriate for delicate soups such as vichyssoise. *

Questions should be addressed to Ask Martha, care of Letters Department, Martha Stewart Living, 11 W. 42nd St., New York, NY 10036. Questions also may be sent by e-mail to: mslletters@marthastewart.com. Please include your name, address and daytime telephone number.