Would you like a bag for that?

NON-FICTION: The Checkout Girl: My Life on the Supermarket Conveyor BeltBy Tazeen Ahmad Friday Instants/Harper Collins, 262pp. £10.99

HERE WE GO again. Journalist takes up unusual job for a short period and writes a book about the experience. In the case of The Checkout Girl,Channel 4 presenter Tazeen Ahmad goes undercover at a large branch of the British supermarket chain Sainsbury's. She joins a small army of part-time workers that includes women who just need to get away from their family for a few hours as well as an executive who has lost his job and is trying to carve out a new career through the aisles. The book's subtitle, My Life on the Supermarket Conveyor Belt,says it all. This is a day-by-day account of Ahmad's time at the checkout, shuttling between the dreaded Till 6, positioned right in front of the supervisor's desk, and the gulag of Till 27 where COGs – checkout girls – can pass their time staring into space, unchecked.

Ahmad came up with the wheeze last November when recession loomed over the UK and though she may have had a book deal under her belt, the prospect of earning an extra £6.30 per hour may have been part of the appeal. Things, she observed, were about to “get rocky for every man, woman and child in this country”. In the supermarket world that means price wars. Discount stores such as Lidl, Aldi and the British chain Morrisons are gaining ground. Sainsbury’s is positioned in the sagging middle of the market, not as cut throat as Tesco but not as posh as Waitrose.

Sainsbury’s has Jamie Oliver and its Anya Hindmarch I Am Not a Plastic Bag totes, but best of all, its reputation for friendliness which it goes to scary lengths to maintain. Checkout girls are constantly monitored to see if they are smiling enough, and being chatty to customers. Supervisors stalk the floor, observing their every move, and giving regular feedback. The carrot is the possibility of a “shining star” for service, the stick is the constant threat of a visit from a mystery shopper. A bad mark from one of these and there’s no bonus.

At first Ahmad does her very best to be the brightest, most friendly of all cogs, keeping up a relentless flow of chat about the weather, the price of everything and the best way to cook meatballs, all the while concealing a notebook in which she jots down what people are saying and what they are buying. No big surprises: hair dye kits are flying out the door, young men buy a lot of Lynx and fat people fill their baskets with chocolate. So far, so predictable. Soon though she realises that habits are changing: shoppers are getting tetchier; they’re buying cheaper and cheaper food and they cut out a lot of coupons. Also, they’re not always right. In fact they’re a rude lot, and sometimes foul-mouthed with it. Her breezy invitations to chat are often rebuffed, sometimes she is completely ignored, and regularly the worst thing of all happens – when she asks a shopper how they are today, they actually tell her. And it’s not good. More and more of them are losing their jobs, some are losing their minds. The sad, depressed and the destitute pass through her till, and as the months go by, Ahmad’s position hardens. She tires of wittering women who say, “How much? I only came in to get a hair dye kit! How could I have spent £132?” Most of all she wearies of the men who titter when she says, “just put it in there . . .” meaning their chip-and-pin card into the machine. The funniest part of this book is when she writes open letters to vent her frustration – to the control freak wives who won’t let their husbands pack, to the paranoid lot who go into contortions as they enter their pin number, and most of all to the supermarket bosses who ignore the supremely bright, sassy women who run the checkouts.

Orna Mulcahy is an Irish Timesjournalist