Avoiding Cross-Contact

Learn how to prevent cross-contact, which happens when an allergen is accidentally transferred from one food to another.

Cross-contact happens when one food comes into contact with another food and their proteins mix. As a result, each food then contains small amounts of the other food. These amounts are so small that they usually can’t be seen.

Even this tiny amount of food protein has caused reactions in people with food allergies! The term “cross-contact” is fairly new. Some people may call this “cross-contamination.”

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    Understanding the difference between Cross-Contamination vs. Cross-Contact

    When dining at a restaurant, you will need to have a discussion about cross-contact with one of the restaurant employees. Even though food allergies are commonly understood, the term cross-contact is fairly new. You may know the term and how to safely prepare an allergen-free meal, but this term is still not universally used in the food service industry. The commonly used term is cross-contamination. Foodservice employees are trained to prevent foods from being contaminated by biological contaminates. Once you know the difference it will be easier to discuss this at the restaurant. 

    Cross-contamination is a common factor in the cause of foodborne illness. Microorganisms such as bacteria and viruses from different sources can contaminate foods during preparation and storage. Proper cooking of the contaminated food in most cases will reduce or eliminate the chances of a foodborne illness.

    Cross-contact occurs when an allergen is inadvertently transferred from a food containing an allergen to a food that does not contain the allergen. Cooking does not reduce or eliminate the chances of a person with a food allergy having a reaction to the food eaten. 

    As you can see, many food service employees will hear you say cross-contact, and may think this is the same thing as cross-contamination. It is your responsibility to explain the difference to them.

    Examples of Cross-Contact and How to Avoid It

    Say a knife that has been used to spread peanut butter is only wiped off before being used to spread jelly. There could be enough peanut protein remaining on the knife to cause a reaction in a person who has a peanut allergy. All equipment and utensils must be cleaned with hot, soapy water before being used to prepare allergen-free food.

    Even a trace of food on a spoon or spatula that is invisible to us can cause an allergic reaction.

    View more examples of cross-contact >

    Talking to Restaurant Personnel about Cross-Contact

    It is important to be aware of cross-contact when dining out. A good example of this is the use of a flattop grill. During breakfast the grill may be used to scramble eggs and cook French toast, so the grill would contain egg, milk, and wheat proteins. During lunch, the grill may be used to cook meats. These items may not contain egg, milk, or wheat proteins, but if the grill was not properly cleaned before lunch, the allergens would still be present. These meats would now come in contact with these proteins and be contaminated. Be sure to speak to a manager about their procedures for cooking allergen-free meals. 

    Do not be nervous about calling a restaurant you would like to dine at. The chef and managers appreciate your call. They do not want to do anything to cause you an allergic reaction. The best time to call is between 2:00 pm and 4:00 pm, when most restaurants are not as busy. If the chef or manager is not available, ask for the chef or manager’s name and the best time to call back. 

    A simple way to communicate information with restaurant chefs and managers is with "Food Allergy Alert" Chef Cards that outlines the foods you must avoid or using a Teal Ticket.  MyTealTicket is a restaurant order form that helps people with food allergies have a safe and enjoyable dining experience. The teal color stands out from all of the other restaurant order tickets, which will make it easier for the chef as he or she prepares your meal.

    Questions to ask the chef or manager about cross-contact

    • Do you have a separate area to prepare foods for special diets?
    • Do you have separate cutting boards and utensils to prepare my meal on?
    • Do you use a shared grill and/or fryer for cooking regular meals and allergen-free meals? If the answer to this question is yes, the restaurant does not understand food allergies.
    • Who will be preparing my meal? Servers should not prepare any part of your meal. Ladles and tongs used for serving soups and salad ingredients can be inadvertently placed back with the wrong food. This could cause your meal to come in contact with other foods you may be allergic to.
    • How will my meal be labeled and delivered? It should be delivered separately, preferably by the chef or manager. Many servers balance several plates on their arms, or set several plates overlapping on a tray. You do not want your plate next to another plate that might contain an allergen.
    • Can my table be sanitized?

    Read more tips for dining out>

    Effective Cleaning

    To effectively remove food protein from surfaces, wash the surfaces with soap and water. Simply wiping the crumbs from spatulas, cookie sheets, cutting boards, or surfaces is not enough. To be safe, purchase a cutting board, plates, and kitchen utensils that will be used for allergy-free foods only. Store these items in a designated area.

    Studies have shown that conventional cleaning methods are effective in removing the protein of a food allergen such as peanut. Bar and liquid soap is effective for removing protein from your hands, while alcohol-based sanitizer is not, according to a study published in the Journal of Allergy and Clinical Immunology;. That study also showed soaps and commercial cleaning agents effectively removed peanut protein from tabletops, while dishwashing liquid alone did not. 

    One tablespoon of concentrated bleach per gallon of water at normal room temperature is the standard for cleaning food preparation surfaces. Hotter water temperatures decrease the effectiveness of bleach solutions. Putting the solution in a spray bottle is convenient for travelling. Allow the surface to air dry after sanitizing. The effectiveness of a bleach solution diminishes over time.

    Smart Cooking at Home

    When cooking allergen-free meals, use utensils and pans that have been thoroughly washed with soap and water. If you’re cooking several foods at the same time, cook the allergen-free meal first. Keep it covered and away from any splatter that may be caused by other foods that are cooking. If you have handled an allergenic food, wash your hands with soap and warm water before serving the allergen-free meal.

    Schaefer, J; Serving People with Food Allergies: Kitchen Management and Menu Creation: CRC Press 2011

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