WE MET in Exotic Fruit. I had first seen him in Green Vegetables, our eyes had - possibly - met, but we finally spoke over the Honeydew Melons. When he stopped by the counter, I had one melon in each hand, holding them up as though to imitate someone with huge bosoms. I offered them to him. 'How can you tell if these are ripe?' I asked. He looked at me quickly. 'I was about to ask you that,' he replied, giving the fruit little squeezes with his thumbs. My heart quickened.

We discussed how, and in what places, one should palpate a ripe melon, and the perfect partnership it makes with prosciutto crudo. Things seemed to be going well when an avocado caught his attention and, without a word, he disappeared into Salad. The next time I saw him he was hurrying to the check-out, and scarcely returned my candid smile.

It is some time since Armistead Maupin brought the exotic world of supermarket dating to our attention in his San Francisco saga, Tales of the City. 'Social Safeway,' Connie the air hostess explains to her appalled novice, Mary Ann Singleton. 'It's the hottest thing in town. And you don't even have to look like you're on the make.'

The idea of intimate moments stolen in the supermarket, that bastion of impersonality, held an irresistible appeal. Suddenly you could be attractive while pushing a supermarket trolley.

The chattering classes became obsessed with the idea. A casual mention of grocery shopping elicited detailed information: Robert recommended the deli counter at Waitrose in the King's Road; Nigel said Tesco's in Brixton was always busy on Tuesdays; Sally was certain she had been chatted up in TV Dinners. The whole city it seemed, was to be found mincing and giggling from New Potatoes to Fresh Fish, and practically snogging by the time they got to Desserts.

Well, it wasn't at all like that in Stamford Hill Safeway, north London. I had set off across town to discover the truth, armed with tips on what my basket should contain if I was to give an impression of a solitary and sensuous life. One of everything. Absolutely no items of personal hygiene. Expensive cat food only. No family packs.

At a Sainsbury's in Camden on a Friday night people were shoving things in plastic bags as though their lives depended on it. I tried to look as though shopping was the last thing on my mind. A couple barged past me, he pushing the trolley, she steering the front end with an iron grip. I had been told that the food in one's basket could indicate one's sexual proclivities, like a sort of foodie bumper sticker ('Vegetarians do it in the garden'). I selected an avocado, a bunch of white grapes and a four-pack of Rolling Rock, on aesthetic grounds. A handsome man with a ponytail loitered at the cheese counter, but as I composed my opening gambit his wife swooped, dropping her prizes in his waiting arms.

Sainsbury's in Islington on Wednesday night was more encouraging. In Fresh Produce, two men were poring with exaggerated enthusiasm over a recipe book. But when I casually asked a young man whether he could tell me which mozzarella was better, buffalo or cow, he said rudely: 'Why don't you try them both?'

It was in Waitrose in the King's Road that the melon encounter took place. You get a better class of shopper in Chelsea, and in spite of early rejection, things were looking good. In the wine department the cashier, suspicious at my repeated, fruitless visits, pinned herself to my side on a pretext of tidying bottles. I shook her off in time to catch a beautiful man lingering over the New Zealand wine rack. 'Do you know anything about these?' I asked. 'Well, I do know quite a lot,' he said, smiling modestly. 'What are you looking for?' I nearly swooned. His dark eyelashes practically grazed mine. 'Something young and fruity? Or stronger and mature . . .' 'I didn't think I'd ever catch you drinking New Zealand wine,' said a young man with blond hair and a light antipodean accent, wandering up to join us. 'Some things from New Zealand are all right,' said his friend, grinning. (Readers of Tales of the City may remember this is exactly what happened to Mary Ann Singleton in Social Safeway. Readers may also remember how she felt.)

In Brixton Tesco's, I asked the security guard if he had noticed any unusually social activity among customers. 'Oh yes,' he said, 'they come in here all the time and hang about. We can't throw them out.' At last, I thought, I have tracked down the supermarket mating ritual. 'Oh yes,' the guard went on, 'the over-60s, they've got nowhere else to go.'

Cullen's in Holland Park out west is fertile ground: there are no humdrum items and all the food is designed for single people who can't cook. I stood in front of a bewildering range of soups and a fat, bald man stood beside me. I told myself this was the pursuit of Truth. 'Have you tried this one?' I inquired, proffering New French Onion. 'I was just about to ask you the same thing,' he replied, wielding Crab Chowder. Bloody men, I thought. Always wait for you to make the first move. 'Why don't you try that one and I'll try this one,' he said, 'and then next time . . .' So that was it. A protracted campaign, a supermarket soap opera. Who did he think we were, the Gold Blend Couple?

On Saturday, Tesco in Covent Garden was packed, and everyone was behaving very strangely. One man with an empty basket went and stood in Toiletries. Another stood, rooted, by the bread. Two men walked slowly, very close together, along the raw meat, commenting loudly on every cut.

I asked a friend to decode this peculiar behaviour. 'Supermarket shopping? It's highly sexed,' he said. 'The things people wear . . . like really short shorts. It's been around for a long time in the gay community. If you see someone you like you go to a part of the store where it's really obvious you aren't going to buy anything, like . . . baby things. If you don't fancy them it's easy to get away. It's all on sale, isn't it? Love for sale.'

But how is it done? I had never got beyond the subject of food. 'You say: 'Oh, hi'. They go: 'Oh, hi'. If they're on to you they say: 'What are you doing later?' '

So subtlety was out. My dopey questions about cheese just made me sound like a mad woman. When there's room in my fridge, I'll try a more forward approach.