Pride is one of the seven deadly sins and, after a visit to the venerable Castle Hotel in Taunton, I know why. It is currently celebrating the 50th anniversary of its management by the Chapman family, and in each of the bedrooms is a glossy document attesting to the glories and triumphs of the place. To read it, you would think they had discovered a cure for cancer, not just run a nice hotel in a pleasing West Country town for longer than average.

It is also a rather bitchy piece of work. In March of this year, Phil Vickery, the hotel's former chef, took the Castle to an industrial tribunal claiming unfair dismissal, having been sacked the year before. The case turned on whether Vickery, who had become a TV chef and started a relationship with Fern Britton, had been paying enough attention to his duties. The tribunal found in his favour but, as the brochure reports, not once but twice, held that he was 50 per cent to blame for his own departure. 'He was subsequently awarded somewhat less than the severance deal he had originally been offered,' the author sniggers.

So my teeth were already on edge, even before I got anywhere near the restaurant. They then nurtured my irritation by giving me the very worst table in the room, the only one right next door to the endlessly flapping kitchen doors. Perhaps they thought that, as the only solo diner that night, I wouldn't complain. I promptly asked to be moved to another table in the quarter-full room. After much list consulting, they found another which, happily for me, was next to the table where the current boss, Kit Chapman, was soon seated with his wife.

It gave me the opportunity to watch the Chapmans at work. Shortly, they were to be found chatting amiably with two elderly guests nearby. Indeed, being such close friends, they invited them to spend Christmas 2001 with them as their private guests. And then, the moment the couple had left the room, they dispatched a member of staff to find out the names of the people they had just embraced. This is, depending on your point of view, either the work of a consummate hotelier or merely an act of startling insincerity, though probably the one demands the other. At the very least, they could have had the wit not to do it in front of other guests.

Around the Chapmans' table the waiters descended to straighten glasses and fold napkins and to generally attend to the governors' desires, while ignoring the bloke sitting to their side with his empty wine glass. My half bottle of Gewürztraminer was in an ice bucket on a table way down the other end of the room. I eventually grabbed a waiter's attention and pointed out the winelessness of my glass. 'Which wine are you having?' he asked. I told him to work it out for himself. He came back with a big grin. 'Found it.' Ah, he must have been so proud.

The real shame about all these niggling, tiresome details, the things that can turn a great night out into an irritating bore, is that they detract from the food of chef Richard Guest, which is worth the trip. Kit Chapman has long been a champion of British food - he employed Gary Rhodes early in his career - and Guest is continuing the tradition. At dinner, there is a three-course menu at £31. It began with a teacup full of intense and creamy seafood soup, with the requisite frothy head. For my starter, I chose a chicken and leek sausage on a warm salad with what was described as 'salad cream'. This was more of an acidic mayonnaise than anything resembling the yellow scum served up for so long with school dinners. Thank God. It was a fine, if slightly low-key, dish.

For the main course, I had the 'Celebration of British Beef', which is about as close to a political statement on a plate as I have ever eaten, and a grand one at that. If it has a fault, it lies in overkill: there was a fine disk of fillet with a (slightly redundant) lamb sweetbread on top, a chewy, caramelised hunk of oxtail, a beef olive stuffed with a dice of offal and, on the side, a small bowl of consommé with tongue. And it came with roast parsnips, wilted spinach, pommes purées and a rich, meaty gravy, and was pretty much the last word in nose-to-tail eating. If you like beef, it's close to perfect.

I finished with a chocolate orange fondant sponge with white chocolate ice cream, a dish that should be barred to those who have just had the beef, because it's way too much and, though thick and toothsome, it defeated me. The problem is that what I take away from my stay at the Castle is not the memory of this food; it's the smugness of the literature, the distracted air of some of the staff and the Chapmans being so ungraciously gracious. That's what leaves a sour taste in the mouth.

• The Castle Hotel, Castle Green, Taunton Somerset (01823 272 671). Dinner for two, including wine and service, around £100. Contact Jay Rayner on jay.rayner@observer.co.uk.