Sinking my teeth into the lemon, I braced myself to wince at the sour, citric tang that would inevitably assault my taste buds. But, almost unbelievably, there was not a hint of bitterness. The acidic fruit tasted as sweet as lemon meringue pie.
The sensation was surreal, as if I were sampling the result of some worrying genetic modification. Yet it was 100 per cent natural, the incredible effect of the 'miracle berry' that has become the most fashionable fad among the foodie set.
Claims of how the red berries of the West African Synsepalum dulcificum bush could play tricks on the tongue seemed too good to be true. So, armed with a 2gm bag of freeze-dried berries, which sells for £6, and with the aid of Michelin-starred chef Aiden Byrne, I put this 'wonder food' to the test.
We needed just a tiny spoonful of the inky-red powder, swirling it around our mouths to ensure all of our taste buds were coated. For all the effects it has, the slightly acidic flavour of the wonder food itself is rather disappointing.
But both Aiden and I felt our saliva glands working overtime in response to the miraculin, the protein within the berries that temporarily masks the tongue's ability to taste sour flavours.
This isn't necessarily a good thing for a chef, as Aiden found when he tried to make a fennel risotto under its influence. Even after drowning the rice in lemon, he thought the dish was way too sweet, and I agreed. It was down to his sous chef at The Dorchester in London to tell us it was too sour to be edible - and chuck it in the bin.
Next, a salt-cod mousse tasted delicious, just as it was supposed to, but the red-pepper and pork-belly accompaniment, as sampled under the influence
of the wonder berry, would have been more appropriate on the dessert menu.
The 35-year-old chef brought out one final dish, a peanut butter and banana dessert with roast pineapple and palm-sugar ice cream. The sugar rush exploded in our heads as the naturally sweet taste of the fruit was magnified 100-fold. But although it was almost impossibly sweet, there was none of the artificial after-taste you might normally expect from something so potent.
Our next stop was F Cooke's pie-and-mash shop in Hoxton in the East End of London, where I was to try jellied eels for the first time.
As a Northerner, I found the prospect of the East End delicacy pretty repellent, so I decided to douse the eels in fiery chilli vinegar - a traditional accompaniment.
Despite my reservations, the result tasted amazing. The sharpness of the vinegar was completely masked. I could drink it on its own and it tasted as sweet as home-made lemonade.
Shop owner Joseph Cooke was shocked. 'I don't know how you can do that,' he said. 'Only a loony would drink it neat - it's so hot.'
I rounded off the meal with a selection of fruits. An ordinary apricot was almost as sugary as a spoonful of golden syrup and a plain natural yogurt was richer than any dessert I'd previously tasted. It was like spoonfuls of pure double cream - but without the calories.
I completed the taste test with the strongest, smelliest cheese I could find, a potently acidic Spanish one called Cabrales, almost solid with blue veins.
Although it was still quite tangy, there was a creamy flavour to it, which I was certain would disappear when the remarkable effects of the berry wore off.
The miracle ingredient had more than lived up to its hype, so it's no wonder that interest in it is snowballing.
Adam Morris, who imports the berries, said: 'People are going to choose the natural alternative to chemical sweeteners. Customers think it sounds interesting and we've had quite a few enquiries from diabetics.'
Another supplier, Chas Barr, 28 said he was sending the berries to 'a lot of very posh addresses...certainly some senior members of the aristocracy'.
It might have taken nearly 300 years since the bushes on which they grow were first documented by the French explorer Chevalier des Marchais, but those wonder berries are becoming increasingly popular. For importers such as Adam and Chas, the future could be very sweet indeed.