Module 5: Cross-Contamination Prevention

What is Cross-Contamination?

Cross-contamination (also called cross-contact) is the transfer of allergens from one food to another. This doesn't just happen in the kitchen — FOH staff can cause cross-contamination too.

How FOH Can Cause Cross-Contamination

Carrying dishes: An allergen-containing dish splashes or touches a safe dish on the same tray
Shared utensils: Using the same tongs, spoons, or serving tools for different dishes
Hands: Touching allergen-containing food then handling a safe dish without washing hands
Surfaces: Placing a safe dish on a contaminated counter or tray
Drinks: Using contaminated equipment for drinks (e.g. milk residue on a steam wand)
Wrong dish delivery: Delivering the wrong dish to the allergy table

Remember Even microscopic amounts of an allergen can trigger a life-threatening reaction. You cannot see, smell, or taste cross-contamination.

Cross-Contamination Risks at RaRa

These are real examples from the RaRa kitchen that you need to be aware of:

Situation	Allergen Risk	Why It Matters
Same tongs used for different dishes	Any allergen	If tongs touched a prawn dish, they now carry crustacean allergens to the next dish
Grilling fish & meat on the same grill	Fish	Fish proteins transfer to the grill surface. Meat cooked on the same grill is no longer fish-free.
Frying chicken karaage in oil used for ebi krokette	Crustaceans	Prawn (crustacean) proteins remain in the frying oil. The karaage is no longer crustacean-free.
Handling prawns or peanuts then touching other food	Crustaceans / Peanuts	Allergen proteins on hands transfer to everything touched afterwards
Sesame oil splatter near other dishes	Sesame	Even a tiny splash of sesame oil contaminates a dish for a sesame-allergic guest

FOH Awareness You won't always see these kitchen risks directly, but you need to understand them so you can explain to guests why certain modifications aren't possible. For example: "We fry multiple items in the same oil, so we can't guarantee a crustacean-free fryer."

FOH Safe Serving Rules

1

Deliver allergy dishes separately Do not carry an allergy-safe dish on the same tray as allergen-containing dishes. Deliver it separately or carry it by hand.

2

Wash your hands If you've handled allergen-containing food (e.g. cleared plates with prawn dishes), wash your hands with soap and water before handling the allergy-safe dish.

3

Check the dish at the pass Before picking up an allergy dish, confirm with the kitchen: Is this the allergen-free dish? Is the red card on the tray?

4

Deliver to the correct guest Use the red card stand to identify the allergy table. Verbally confirm with the guest. Never rely on table position alone.

5

Never "pick off" an allergen If the wrong garnish or ingredient was added, the dish must go back to the kitchen. You cannot remove an allergen — cross-contamination has already occurred.

Golden Rule If an egg was placed on a bowl for a customer with an egg allergy, you cannot simply remove the egg. Cross-contamination has occurred. The meal must be started again from scratch.

Drinks and Beverages

Cross-contamination can happen with drinks too. Be aware of these risks:

Situation	Risk	What to Do
Coffee machine steam wand	Retains milk residue even after purging. Cross-contamination between dairy, soy, almond, and oat milk.	Inform the guest that complete allergen removal is difficult. Let them decide.
Shared blenders	Residue from previous blends can remain	Use a thoroughly cleaned blender or a separate one for allergen-free drinks
Garnishes	Nut garnishes, sesame, or other allergens added to drinks	Check before serving. Leave off garnishes for allergy guests.

Cleaning vs Sanitising: What You Need to Know

Critical Distinction Cleaning (warm water + detergent + clean cloth) removes allergens. Sanitising alone does NOT remove allergens. You must clean FIRST, then sanitise.

	Removes Allergens?	Use For
Cleaning (warm water + detergent + clean cloth)	YES	Surfaces, utensils, trays before handling allergy orders
Sanitising (chemical spray or wipe)	NO (on its own)	After cleaning, for food hygiene
Hand sanitiser	NO	Not a replacement for handwashing
Wiping with a tea towel	NO (can spread allergens)	Never use for allergen cleaning

FOH Handwashing If you've been clearing tables with allergen-containing dishes, you MUST wash your hands with soap and warm water before handling any allergy-safe food or drinks. Hand sanitiser is not enough.

Flashcards

Click each card to reveal the answer.

Why can't you fry karaage in the same oil used for ebi krokette for a crustacean-allergic guest?

Click to flip

Prawn (crustacean) proteins remain in the frying oil. The karaage cooked in that oil is no longer crustacean-free — cross-contamination has occurred.

Can you pick off an allergen (e.g. remove an egg) and still serve the dish?

Click to flip

NO. Cross-contamination has already occurred. The meal must be started again from scratch with clean equipment.

Does hand sanitiser remove food allergens?

Click to flip

NO. You must wash hands with soap and warm running water. Hand sanitiser does not remove allergen proteins.

Does sanitising a surface remove allergens?

Click to flip

NO. Sanitising alone does not remove allergens. You must CLEAN first (warm water + detergent + clean cloth), then sanitise.

Why is grilling fish and meat on the same grill a problem?

Click to flip

Fish proteins transfer to the grill surface. Meat cooked on the same grill afterwards is no longer fish-free. This is cross-contamination.

Knowledge Check

1. You're about to deliver an allergy-safe dish but you just cleared a table that had prawn tempura. What should you do first?

Use hand sanitiser and pick up the dish Wipe your hands on your apron Wash your hands thoroughly with soap and warm water before handling the safe dish

Correct! Hand sanitiser does NOT remove allergens. You must wash with soap and warm water before handling allergy-safe food.

Incorrect. Neither hand sanitiser nor wiping removes allergens. You must wash with soap and warm running water.

2. A sesame garnish was accidentally added to a dish for a guest with sesame allergy. You remove the seeds. Is the dish safe?

Yes, the sesame has been removed No — cross-contamination has occurred and the dish must be remade from scratch Only if you wipe the surface of the dish

Correct! Once an allergen has touched the food, cross-contamination has occurred. The dish must be remade from scratch with clean equipment.

Incorrect. Removing the allergen is NOT enough. Sesame oil and proteins have already transferred to the food. It must be remade.

3. A guest with a crustacean allergy orders chicken karaage. The kitchen fried ebi krokette (prawn) in the same oil earlier. Is the karaage safe?

Yes, karaage is chicken not prawns No — prawn proteins remain in the oil, making the karaage unsafe for a crustacean allergy Yes, the oil was hot enough to destroy allergens

Correct! Crustacean (prawn) proteins remain in the frying oil. Cross-contamination means the karaage is NOT safe for a crustacean-allergic guest.

Incorrect. Heat does NOT destroy allergens. Prawn proteins remain in the frying oil and contaminate anything else cooked in it. The karaage is not safe.

4. What is the correct method for removing allergens from a surface?

Sanitising spray only Clean with warm water, detergent, and a clean cloth first, then sanitise Wipe with a damp tea towel

Correct! Physical cleaning with warm water, detergent, and a clean cloth removes allergens. Sanitising is for hygiene but does not remove allergen proteins on its own.

Incorrect. You must CLEAN first (warm water + detergent + clean cloth) to physically remove allergen proteins, then sanitise for hygiene.