Singles have adopted a whole new set of dating rules coupled with an intricate system of code to communicate with each other across the fresh produce displays.
American anthropologists have even coined a phrase for it — "trolleyology" — and local cultural experts say for those in on the game it's quickly becoming impossible to observe the contents of a fellow shopper's trolley casually without at least wondering if you might have found your perfect match.
—Chris Taylor, Love in the aisles," Sunday Mail, November 24, 2002
A person who buys fish fingers is likely to be boring in bed, while someone who stocks up on stir-fry vegetables is bound to be an experimental lover. "It is called 'trolleyology' - making judgments about people from their shopping," says top consumer psychologist Dr David Lewis, who conducted a survey for supermarket chain Somerfield.
Now single men and women wanting to send out messages to potential partners could use the research to their advantage.
"A woman wanting to give the impression she is uninhibited and likes to party should fill her trolley with chocolate fudge cake, bananas for energy and a box of wine," says Dr Lewis. "These all send out the signal that 'I'm a party animal and I just want to have fun'."
But, he adds: "A man who wants to convince people he loves the country and finer things in life should buy plenty of smoked salmon, brandy and tins of dog food.
"If he wants to show he is steady and reliable, he should heap his trolley with Brussels sprouts." One woman in the survey admitted that a glance into a man's trolley tells her all she needs to know. "I saw a really good-looking man in my local supermarket recently," she says.
"But I was turned off when I peered into his basket and realised it was packed with lager and frozen hamburgers. He smacked of being a slob who spent his life in front of the TV watching football."
Trolleyology is a real craze in America, says Dr Lewis.
—Samm Taylor, "Shopped by your trolley," The Mirror, January 30, 1997