Here's what happens in the kitchen when you tell a restaurant you have an allergy

A waiter's arrest after a customer suffered a near-fatal allergic reaction from an order mix-up has restaurants wanting to demonstrate they take food allergies seriously.

When a customer with a food allergy walks into Restaurant Gus, a trendy spot on Beaubien Street East in Montreal, the kitchen staff wants to know two things: the severity of the allergy and whether it's a contact allergy.

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Some food allergies are triggered by eating something in particular, which is generally easy enough to accommodate, said the restaurant's owner and chef David Ferguson.

But a contact allergy requires added vigilance. These are allergies that can be triggered simply by traces of an allergen. Knives or cutting boards can transfer traces of certain foods if not washed properly.

"Whenever there is an allergy, we wash everything," Ferguson said. "But if it's contact, we really have to make sure everything is washed."

'Everything is washed'

The process is straightforward. Soap is applied directly to a knife before it is used to prepare a meal for a client with an allergy. The knife is scrubbed and then rinsed off. 

The same applies to other kitchen implements, especially a cutting board. 

"Just last week somebody told me, as they were about to eat their tomato salad, that they were allergic to mangoes," Ferguson said.

"I had already made the tomato salad. I had wiped [the cutting] board, but I hadn't washed it before making the tomato salad. So I had to make them a new tomato salad."

Servers at Restaurant Gus are encouraged to always check with the kitchen staff after they are informed of a customer's allergy.

Recipes can change: A dish that was once safe for an allergic customer may no longer be so after new ingredients are added.

"We always tell our servers ... to come back to the kitchen to make sure," Ferguson. "That's the best way to keep things clean and organized to help people with their allergies. 

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