Q: What is listeria? How can I safely handle refrigerated ready-to-eat foods to avoid it?

A: Listeria monocytogenes is a bacterium that can cause a serious infection in humans called listeriosis, which results in an estimated 2,500 serious illnesses and 500 deaths each year. Foodborne illness caused by L. monocytogenes in pregnant women can result in miscarriage, fetal death and severe illness or death of a newborn infant. Others at risk for severe illness or death are older adults and those with weakened immune systems.

Because L. monocytogenes can grow at refrigerator temperatures and is found in ready-to-eat foods, the FDA advises all consumers to reduce the risk of illness by:

¢ Using perishable items that are precooked or ready-to-eat as soon as possible;

¢ Cleaning their refrigerators regularly; and

¢ Using a refrigerator thermometer to make sure that the refrigerator always stays at 40 degrees or below.

Since pregnant women, older adults and people with weakened immune systems are at higher risk for listeriosis, FDA recommends the following for at-risk consumers:

¢ Do not eat hot dogs and luncheon meats, unless they are reheated until steaming hot.

¢ Do not eat soft cheese such as feta, Brie and Camembert cheeses, blue-veined cheeses and Mexican-style cheeses such as “queso blanco fresco.” (Cheeses that may be eaten include hard cheese; semi-soft cheeses such as mozzarella; pasteurized processed cheeses such as slices and spreads; cream cheese and cottage cheese.

¢ Do not eat refrigerated pates or meat spreads. (Canned or shelf-stable pates and meat spreads may be eaten.)

¢ Do not eat refrigerated smoked seafood, unless it is contained in a cooked dish, such as a casserole. Refrigerated smoked seafood, such as salmon, trout, whitefish, cod, tuna or mackerel, is most often labeled as “nova-style,” “lox,” “kippered,” “smoked” or “jerky.” The fish is found in the refrigerator section or sold at deli counters of grocery stores and delicatessens. (Canned or shelf-stable smoked seafood may be eaten.)

¢ Do not drink raw (unpasteurized) milk or eat foods that contain unpasteurized milk.

Q: How does marinating tenderize meat?

A: The marinade’s acid chemically softens the connective tissue in meats. To be effective, sufficient marinating time is necessary. Most dishes require an hour to overnight, depending on the food.

Always remember to marinate foods in the refrigerator. Bacteria grow rapidly at room temperature. The acid in marinade doesn’t kill bacteria; it merely slows or stops bacterial growth.

Marinade that has been used on raw meat, poultry and seafood contains raw juices. These juices may contain bacteria that, if eaten, could make you sick. Discard the marinade promptly after use.

Q: Are there nutritional differences between fresh foods and canned foods?

A: The heating process during canning destroys from one-third to one-half of vitamins A and C, riboflavin and thiamin. For every year the food is stored, canned food loses an additional 5 percent to 20 percent of these vitamins.

However, the amounts of other vitamins are only slightly lower in canned food than in fresh food.

Most produce will begin to lose some of its nutrients when harvested. When produce is handled properly and canned quickly after harvest, it can be more nutritious than fresh produce sold in stores.

When refrigerated, fresh produce will lose half or more of some of its vitamins within one to two weeks. If it’s not kept chilled or preserved, nearly half of the vitamins may be lost within a few days of harvesting. For optimum nutrition, it is generally recommended that a person eat a variety of foods.

Q: Does freezing affect the level of nutrients contained in foods?

A: Fortunately, the freezing process itself does not reduce nutrients, and, for meat and poultry products, there is little change in protein value.

Q: How should you select and use cutting boards?

A: Cutting boards can harbor bacteria in cracks and grooves caused by knives. But with little effort, plastic, a hard wood, such as maple, or any nonporous surface can be used safely if used properly. Here’s how:

¢ Choose a good surface: Select a board that can be cleaned easily, that is smooth, durable, and nonabsorbent. Plastic is less porous than wood, making it less likely to harbor bacteria, and easier to clean.

¢ Wash your board: Wash your cutting board with hot water, soap and a scrub brush, to remove food and dirt.

¢ Sanitize your board: After washing it, sanitize your board in the dishwasher or by rinsing it in a dilute chlorine bleach solution of 1 tablespoon bleach to 1 gallon water.