SEATTLE -- Tomatoes have topped the news for a couple of days now. And it has people asking about washing produce.

There are many ways produce can be contaminated with bacteria, bacteria that can make you really sick or even kill you. The problem is, you can't smell, see or taste these harmful bacteria.

That's why all raw produce - whether conventionally or organically grown - should be thoroughly washed before eating. You don't need soap or a commercial produce cleaner. According to the UC Berkeley Wellness Letter, there's no evidence they are any better than plain old water.

Cold running water, and a brush for firm produce such as carrots, melons and cucumbers, should get rid of the dirt, bacteria and pesticide residue on the surface.

When you're done, dry the produce with a clean cloth towel or paper towel. That can further reduce bacteria that may be present. Except for bananas, you should wash all fruit even if you plan to peel it before eating. Remember, you need to thoroughly wash your hands with soap and water before you touch any food.

If the bagged lettuce you buy comes pre-washed, there's no need to wash it again. But be sure to check, because not all bagged vegetables come pre-washed.

As for tomatoes, wash thoroughly and cut away the part that's attached to the plant as well as the button on the other side. Those are the places were bacteria are most likely to attach themselves to the tomato.

And people often wonder why they have to wash the melon. That's because it could have bacteria on the rind. The bacteria can get on your knife and when your knife touches the flesh of the fruit, which you'll eat.

That's why you really need to wash all fruit, even if you're going to peel it before you eat it.

Keep it safe when you cook outdoors

When eating outside at picnics and barbecues, outdoor chefs need to be very careful how they handle food and prepare it.

Lisa Lee Freeman, editor in chief of Shop Smart Magazine, said if you're bringing raw meat to the cookout, be sure to seal it very tightly in order to prevent its juices from contaminating other items in the cooler or picnic basket.

"Also what you want to do is never use the same plate - that you're using for your raw food to use it for the finished cooked food, because it can get contaminated," she said.

Freeman says it's also important to keep the marinades used for raw meat away from cooked food. She says to avoid the temptation to pour the leftover marinade on a plate of cooked meat for extra flavor.

"That's terrible. That could make somebody sick because again the bacteria goes from the raw food to the cooked food," she said.

There's one more important rule -- time. Nothing should stay out in the heat for more than two hours, even cooked food. If the temperature hits 90 degrees, that time drops to an hour.

For More Information:

Tomato outbreak is reminder to follow food safety tips

Safe handling of raw produce

Latest Info from FDA about salmonella outbreak in certain types of tomatoes