by Kim Butz, CFSA South Carolina Local Produce Safety Coordinator | Wednesday, Oct. 13, 2021 —
Food allergy spelled out in blocks with allergy food piled behind it (almonds, milk, cheese, strawberry, seeds, eggs, peanuts and  crustaceans or shrimp)

When we think of farming, we rarely associate our farming practices with potentially life-threatening allergens.

Many of the farms I visit are undergoing preparation for their Harmonized GAP (Good Agricultural Practices) certification, and it is necessary to ask if allergens are present on the farm as part of the standard requirements. I often ask this question to my produce farmers while standing next to a chicken coop brimming with eggs or a picture-perfect peanut field. Commonly, I hear back, “no, no allergens on the farm.”

This is not surprising; many do not realize that six out of the top eight allergens can easily be found on a diversified Carolina farm.


Top 8 Heavy Hitter Food Allergens: How Many Are on Your Farm?

Egg, Treenuts, Soy, Shellfish, Fish, Milk, Peanuts, and Wheat

Why is this important, and why is it necessary to consider these allergens while harvesting, packing, and storing your produce?

  • Peanuts
  • Eggs
  • Dairy
  • Wheat
  • Shellfish
  • Fish
  • Soy
  • Tree nuts

These top eight account for 90% of all food allergies. Milk, eggs, peanuts, tree nuts, soy, and wheat are common commodities on the farm. Millions of Americans are affected by food allergies, and the results of interaction can range from mild to life-threatening. I have a friend that is highly allergic to peanuts, and the tiniest ingestion can cause anaphylaxis and death in a very short amount of time.

As you can see, tree nuts, peanuts, and shellfish can be deadly. Those with a food allergy go to great lengths to ensure there are no surprises in the food they eat. They rely on us—food harvesters, packers, processors, and handlers—within the food chain to keep them safe. Unfortunately, cross-contact can happen easily when we unknowingly allow allergens into places where they shouldn’t or wouldn’t otherwise be.


Cross-Contact: What Is It?

Cross-contact happens when we unintentionally transfer an allergen protein to food or food-contact surfaces. This will inadvertently affect a non-allergen food product. Let’s define a food-contact surface. These are surfaces that may come in direct contact with an allergen during production, processing, and packaging. Examples include hands, tools, equipment, trailers, vehicles, and packing/processing tables.


Cartoon of an orange and peanut playing football, and a ref is shouting "allergen control is a no contact sport!'

Source: StateFoodSafety Resources


Cross-Contact: How Does It Happen?

Cross-contact can happen easily. On the farm, there are several ways. Let’s take a look at some possibilities.

  1. Peanut trailers used for seasonal harvest are then used in produce harvest.
  2. Eggs are being cleaned, graded, and sorted on tables that ready-to-eat produce will be processed on.
  3. Soy or wheat is harvested, stored, or transported using the same farm equipment.
  4. Freshly harvested produce in truck beds, trailers, wagons, harvest bins, etc., is held uncovered beneath a canopy of the farm’s nut trees before, during, or after pack.
  5. Fish and seafood are harvested and transported on the same truck as fresh produce.
  6. Cheese and dairy are improperly stored in coolers.
  7. CSA produce boxes (this is a big one) are packed on the same pack line where eggs, bread, dairy products, etc., are also being placed into members’ produce boxes as an added value product.
  8. Employees ate their PB&Js for lunch, then did not properly washing their hands before packing produce.


Harvested peanuts sitting on top of the soil


Cross-Contact: How Can We Prevent It?

Now that we have provided examples of how common practices on the farm can cause unintentional harm, let’s look at some preventative measures that are easy to incorporate into handling practices.

  1. Identify all of the allergens present on the farm.
  2. Provide food safety training for farmers and their employees.
  3. Implement good handling practices and emphasize the importance of allergen control.
  4. Have effective cleaning and sanitizing protocols for equipment and food-contact surfaces
  5. Provide hand washing stations.
  6. Have separate packing, processing, and storage areas
  7. Post proper signage that identifies allergen areas.
  8. Designate employee break areas where personal food is stored and eaten.
  9. Segregate transport.


We can see that our farm practices and the produce we grow and sell can pose a serious threat to those at risk if improperly handled. It is our responsibility to minimize the risk to our customers and provide a safe product.

We hold the keys to the prevention of allergen cross-contact.

The solutions are simple: know your allergens, assess your risks, train you and your employees, and implement good handling, storage, and transport practices on the farm.



If you’re interested in learning more:

Download the 2019 GAP Manual