Safe Food Handler

Cross-contamination is when bacteria is transferred to food via direct contact. In the culinary arts, two of the most common kitchen tools usually tend to be a knife or a cutting board. A food handler with poor personal hygiene can also contaminate food.

However, it is not just bacteria that gets carried from one place to another—it could also be a virus or a toxin of some kind, or even a cleaning product. When it comes into contact with someone's food, it's considered cross-contamination. And if they eat the food and it makes them sick, it is called food poisoning.

Since dangerous bacteria are killed by high heat, the risk of cross-contamination is highest with food that doesn't need to be cooked. That's why outbreaks of salmonella poisoning are increasingly found to be linked to foods like sprouts and bagged salads, foods you might think of as innocuous or "safe" but are risky because they customarily aren't cooked. 

Where Cross Contamination Occurs

Cross-contamination can happen on a very large scale because of equipment at processing facilities not being cleaned properly, for instance, or any of the other numerous ways your food can be mishandled as it makes its way to your kitchen. This is why, from time to time, there are outbreaks of food poisoning, product recalls, restaurant closures, and the like. It is necessary to keep updated and follow exact instructions with the CDC, USDA, FDA and Regulatory Authorities.

Prevention Through Cleanliness 

Ultimately that means that preventing cross-contamination requires building habits such as frequently washing hands, utensils, cutting boards, and work surfaces. For example, if you prep a raw chicken on a cutting board, don't use the same cutting board later to slice tomatoes for the salad. At least not without washing it first. And the same goes for your knife.

This also needs to be practiced when it comes to the food, too. Even if that bagged salad says it's been washed three times, wash it again anyway. Same with sprouts. It can't hurt to wash vegetables even if you're planning to peel them, like carrots—it is an extra step, but when it comes to preventing cross-contamination.

Prevention Through Utensils

Using a set of color-coded cutting boards is a simple method for keeping bacteria from transferring from one surface to another. Many sets come with images (vegetables, chicken legs, etc.) on each board representing which foods to use: green for vegetables and fruits, yellow for raw poultry, red for raw meat, and so on. This way you are one step closer to preventing food-borne illnesses.