It doesn’t seem so long ago, not much more than a couple of years, that Somerfield appeared to be on the verge of a breakthrough when it opened a market-style format. Stores in the south London suburbs of Carshalton and Dulwich were among the chosen few locations that seemed to presage a new form of convenience retailing.

The floors were black terrazzo, there was moody pinpoint spotlighting and there was signage around the upper perimeter that had been printed to appear as if it was hand-written, accompanied by graphics of fresh meat and vegetables.

Then there was the olive oil bar, with large glass bottles of the foodie staple ready to be dispensed into smaller containers on demand. This part of the interior also had half-way decent cheeses and a good selection of cooked meats. All in all, it looked like something new; something that deserved wider exposure.

In the event, Somerfield opted not to go with the format and the interiors have been allowed to drift. Walking into the Carshalton branch on a Sunday, things are much changed. A small portion of the original signage has been maintained. But for the most part, it has been replaced by an entirely utilitarian font and every trace of the graphics with the tasty food has been obliterated.

The deli counter has been taken out and in its place is an upright chiller cabinet that appeared to be leaking, to judge by the wet scrunched-up kitchen towel that had been placed along its base. A good 25 per cent of the shelves were empty and it had either been visited by the whole of south London that day, or the cleaners had been on strike for a week or two.

Finally, there was the cost. Innocent smoothies, always reliably upscale, are on offer at this branch and Somerfield is being considerably more ambitious with its pricing than anywhere else nearby – symptomatic of the rest of its offer. This would not be a problem if the store environment led you to expect you would pay more. It does not. Instead, Somerfield offers its Carshalton customers the worst of all worlds – a dirty, degraded interior with overpriced produce. The supermarket is not even close to being in the big four food retailers' league and, on this showing, it is easy to see why. It is worth noting too that a Tesco Express has just opened not far away. It’s clean, cheap, efficient and has good ranging. Plus ca change…