Cross-Contact: Types and How to Prevent It
Cross-contact is the transfer of food allergens from one surface or food to another food.
It can cause allergic reactions — which may be severe — in sensitive individuals.
As a food handler, it’s your responsibility to prevent cross-contact when preparing an allergen-free order so you can prevent allergic reactions.
This article explains everything you need to know about cross-contact, including how it occurs and what you can do to prevent it.
What is cross-contact?
Cross-contact is the transfer of an allergen from one food to another that would otherwise be allergen-free.
Cross-contamination is similar to cross-contact but occurs with the transfer of a disease-causing organism or pathogen rather than an allergen.
Even tiny amounts of an allergy-causing food or additive — known as a food allergen — can trigger an allergic reaction.
An allergic reaction is an abnormal reaction by the body’s immune system to an allergen.
Of the more than 160 foods and food ingredients known to cause an allergic reaction in sensitive individuals, there are nine that account for 90% of all food allergies.
These nine are known as the major food allergens, and they include (1):
- milk
- eggs
- fish, such as cod, bass, or salmon
- shellfish, such crab, lobster, or shrimp
- tree nuts, such as almonds, pecans, or walnuts
- peanuts
- wheat
- soybeans
- sesame
Like cross-contamination, there are three ways in which cross-contact can occur and cause foodborne illnesses:
- Food-to-food. This type occurs when an allergen-containing food like eggs comes in contact with an allergen-free food like lettuce.
- Equipment-to-food. This type occurs when you use unclean and unsanitized equipment or other food-contact surface to prepare an allergen-free order.
- People-to-food. This occurs when you don’t wash your hands or change your single-use gloves after they become contaminated and then handle an allergen-free food.
Once cross-contact has occurred, you cannot reverse it through cooking or other means.
Summary
Cross-contact is the transfer of a food allergen from one surface or food to another. There are three ways in which cross-contact can occur — food-to-food, equipment-to-food, and people-to-food.
How to prevent cross-contact
Here’s how you can prevent each type of cross-contact:
Food-to-food
Food-to-food cross-contact occurs when an allergen-containing food comes in contact with a non-allergen containing food.
This can happen if you’re preparing a salad and then add diced hard-boiled eggs.
Even if you pick out the hard-boiled eggs, the salad still isn’t safe for someone with an egg allergy since even trace amounts of an allergen can cause an allergic reaction.
The best way to prevent food-to-food cross contact is to keep allergen-free food and orders separate from other orders during both preparation and service.
Equipment-to-food
Equipment-to-food cross-contact occurs when you use unsanitized equipment or other food-contact surface to prepare or serve an allergen-free order.
Buttering a slice of wheat bread and then using the same knife to butter wheat-free bread without first washing and sanitizing it is an example of this type of cross-contact.
Using the same food thermometer to temp a steak that you just used to temp fish is another example of cross-contact.
Always wash and sanitize equipment and other food-contact surfaces like counters, cutting boards, and utensils whenever they become contaminated.
People-to-food
People-to-food cross-contact occurs when food handlers contaminate an allergen-free order.
This occurs when you don’t properly wash your hands or change gloves when they become contaminated.
Assembling a wheat-bread sandwich followed by a wheat-free sandwich without first changing your gloves, washing your hands, and then donning a new pair is a common example of this type of cross-contact.
Remember that gloves aren’t magical and can spread allergens to other food just like your hands.
Summary
To prevent cross-contact, keep allergen-free orders separate from other orders, clean and sanitize your work area, including all food contact-surfaces, and wash and change your gloves.
The bottom line
Cross-contact is the transfer of a food allergen from one surface or food to another food.
The three ways in which cross-contact can occur include food-to-food, equipment-to-food, and people-to-food.
You can prevent cross-contact by keeping allergen-free orders separate from others, clean and sanitize all food contact surfaces, and wash your hands and change gloves.