Heston Blumenthal has been forced to delay the reopening of his restaurant after tests failed to identify the cause of a health scare.

The TV chef temporarily shut The Fat Duck as a precaution after around 40 customers were taken ill over the last couple of weeks.

The ‘culinary alchemist’ had hoped for the all-clear from environmental health officers on Wednesday, but inconclusive test results meant he was unable to reopen the Michelin-starred restaurant in Bray, Berkshire.

The Fat Duck is now expected to remain closed on Friday.

A spokesman said the chef was ‘upset’ and ‘frustrated’ by the health scare. “We are still waiting for the final results to come back but all tests so far have been negative,” the spokesman said.

“Obviously he (Blumenthal) is upset and frustrated. He would like things to get back to normal as soon as possible, but for now his priority is to make sure we get to the bottom of what has happened.”

The investigation, which began after the restaurant was closed last Tuesday, has led to financial losses in the region of £100,000.

About 500 guests had their reservations cancelled at the £130-a-head restaurant. And customers will continue to be turned away until the investigation yields results.

Tests are being carried out on all of Blumenthal’s employees and have led his team to rule out sabotage and the possibility of food poisoning as the cause of the bug.

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