The pastry chef, who is often referred to as ‘Australia’s Willy Wonka’, was unaware his chocolate and tonka bean dessert was “forbidden” until he presented it to the judges Amaury Guichon and Melissa Leong.
“I haven’t tasted tonka in a long time,” Amaury said. “You know it’s actually illegal in the US?
“You cannot import it, you cannot find it anywhere.”
Amaury then described Zumbo’s dish as an “illegal plate”, while Melissa added: “This is a more dangerous plate than you thought”.
“I should’ve called it ‘illegal chocolate’,” Zumbo joked.
Tonka beans have a sweet, spicy flavour similar to vanilla beans with notes of almonds, cinnamon, cloves, caramel and tobacco.
While it’s available to purchase in Australia, the South American legume has been declared illegal in the US as it contains a chemical compound called coumarin which is toxic when consumed in large quantities.
The Food and Drug Administration (FDA) banned all foods containing coumarin in 1954 after researchers found it can cause damage to the heart and liver, and even death in extreme cases.
Despite Amaury’s comments, however, tonka beans still appear on menus in Michelin-starred restaurants across the US, and the country is the world’s biggest importer of the ingredient.
'Stick to the recipe'
Tonka beans first appeared in the MasterChef kitchen in 2009 when Zumbo was a guest judge and featured the ingredient in his panna cotta recipe.
He explained at the time that tonka beans must be treated with respect because they contain coumarin, “which is an anticoagulant and in high doses it thins out the blood to the point where it is dangerous”.
“But we are talking high doses here,” he continued. “You'd have to eat a lot of them for it to be a problem and we use about a quarter of a single bean in any recipe.
“So stick to the recipe, don't go off chewing on them. You only need to shave a little bit of it in.”
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