Preventing Cross-Contact at Home

Food poisoning often is what comes to mind when you hear the words home food safety. But for the millions of Americans with food allergies, celiac disease and many more with other sensitivities, avoiding contact with an offending food is every bit as much of a concern. Coming into contact with a miniscule amount of the offending food may cause life threatening reactions in people with food allergies or cause damage to the intestines of those with celiac disease.

Most of us know someone with celiac disease, gluten sensitivity or a food allergy, so knowing how to keep foods separate when cooking at home is important.

You've probably heard the terms "cross-contamination" and "cross-contact." While used interchangeably, they are two distinct phenomena.

Cross-contamination is when harmful bacteria are transferred to a food from another food or surface. Most dangerous bacteria can be killed through proper cooking.

Cross-contact is when the food allergen or gluten is transferred to a food meant to be allergen- or gluten-free. A key difference is that offending food proteins remain dangerous after cooking.

Safety Starts at the Store

The U.S. Food and Drug Administration's Food Allergen and Labeling Consumer Protection Act and Gluten-Free Food Labeling Rule have made shopping much easier, but care and vigilance is still required:

• When shopping, store problematic foods in plastic bags, place them in a second cart and keep them separate at checkout and in the car.
• Avoid foods from bulk bins, hot/cold salad bars and the deli counter, as these are common sites for cross-contact.
• Read ingredient labels and signage each and every time you shop, as recipes and formulations can change without warning.

Set Up a Storage System

If you can't keep the entire house free from an offending food:

• Cross-contact with an allergen or gluten through condiments is common, due to double-dipping. Choose squeeze bottles when possible to eliminate double dipping. Try to use condiments free from the problematic food for everyone in the family to enjoy, but if this is not possible clearly label the option that is gluten- or allergen-free.
• Dedicate shelves to allergen and/or gluten-free foods to avoid confusion.
• Place gluten- and allergen-containing foods on shelves below allergen/gluten-free foods — in the pantry, refrigerator and freezer.

Conscious Cooking is Key

• Depending on the food that needs to be avoided and where practical, use separate sets of utensils and small appliances such as toasters, pots, strainers, cutting boards, rolling pins, whisks and pizza cutters.
• Prepare and cook allergen/gluten-free dishes first and in/on cleaned equipment and surfaces.
• If possible, dedicate a kitchen space to allergen/gluten-free preparation.

Wash and Wash Again

• Wash and sterilize everything coming into contact with the allergen/gluten-free food being prepared.
• Wash hands with warm, soapy water for 20 seconds.
• Change gloves and aprons.
• Wash plates, small equipment and utensils with hot, soapy water or rinse off residue and put in the dishwasher.
• To clean surfaces and larger appliances, use a dry towel to wipe down crumbs first, then wash or sterilize.

Consider Cross Contact Through Service

• Serve allergen/gluten-free guests first and carry their dishes separate from others.
• For family-style meals, allow guests with allergies/intolerances to serve themselves first.
• Avoid "make-your-own" dishes with high risk for cross-contact, including sundaes, salads and topping bars.

If, after taking all these precautions, you think cross contact has still occurred, let your guest know. They will happily wait to be served a dish that is safe to eat.

Rachel Begun, MS, RDN, is a food and nutrition consultant and writer based in Boulder, CO.