Viewers of Breaking Into Tesco, a TV series on Channel Five, have been entertained as a number of entrepreneurial cooks attempt to win the supermarket group as a customer. There is the soup-in-a-bun man, who has devised a hollow bread roll that can hold soup for five hours without leaking. There is the woman who has created muffins suitable for dogs and human beings.

Mentored by Allan Leighton, the former Asda boss and Royal Mail chairman, they are coached on how to pitch their ideas to the hard-nosed buyers from Tesco. The winner gets a contract to supply the retailer.

What connects the contestants is the belief that winning a supply deal with Tesco is a recipe for riches. It's a given that getting a foot in the door of the supermarket group that accounts for £1 in £8 of all retail spending will inevitably lead to business success.

The profits warning and axed dividend yesterday from Uniq illustrates how winning business from the big supermarkets can instead be the introduction to a world of pain. Uniq is three years into what it optimistically calls its turnaround plan and its shares are pretty much back to where they were three years ago.

Uniq, formerly Unigate, does not have any problem devising, manu- facturing and selling sandwiches and desserts to the likes of Tesco and Marks & Spencer. Revenues last year reached £736million. Its problem is making any profit whatsoever in the process. Resistance in negotiations can be fatal, as when it lost the Sainsbury desserts account last year.

Supermarkets' negotiating muscle is a boon to shoppers, but many suppliers are squealing. With a high street downturn looming, it is hard to see the pressure easing up.

patrick.hosking@thetimes.co.uk

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