The lot of these 3,900 chickens is a relatively happy one. They have 10 acres of Whiteoaks Farm in which to stretch their legs and enjoy the chicken equivalent of a banquet: a mixture of maize, corn, wheat and oats.
For the time being they produce some 3,200 eggs a day. But they may soon have to go into over-drive. Suddenly, the British public has fallen in love with the egg again, and egg farmers are bracing themselves for a surge in demand.
Free-range sales account for 25 per cent of Mr Berry's market, and the turnover in eggs is big business. At his packing plant two miles away 100 staff pack 108,000 eggs an hour, or 8.6 million a week.
Although the UK produces 51 per cent of all free-range eggs in the European Union, and 70.5 per cent of all barn eggs, eggs have not enjoyed a particularly attractive image in recent years. After the salmonella scare of 1988 came health alarms associated with the egg's cholesterol content, and public outrage over battery farms.
But then came Delia Smith. Mention her to Graham Muir, marketing manager of Stonegate Farmers, and a beatific smile plays around his lips. "She's quite an icon, isn't she? She certainly has the power to move things."
Last week Delia moved eggs from supermarket shelves into shoppers' baskets. An extra 1.3 million a day to be precise, thanks to her latest cookery show in which she shows us how to beat, scramble, poach and boil them. Since How to Cook started on BBC2 six weeks ago, an estimated 54 million more eggs than average have been sold - an increase on normal sales of 10 per cent.
This is an overdue boost for the egg. The industry has still not fully recovered from the salmonella scare, with several egg farmers having gone to the wall. Before the scare we ate, on average, three eggs per person per week. Ten years on we still eat less than two eggs a week.
"The egg industry has had to change," says Mr Berry. "It's easy to say everything's down to Edwina Currie but it has taught the industry that the ability to trace the source of an egg and health control are important. We are still recovering but we've had to address the industry's problems."
To this end, a new code has been introduced by the industry umbrella group, the British Egg Industry Council, enabling buyers to trace the egg in the shop back to the chicken in the farm, a similar scheme to that introduced by the beef trade in the wake of BSE. "We know that consumers are genuinely interested in eggs, but in the past 10 years they haven't had any information about the virtues of eggs," says Mr Muir. That will change next year, when the industry launches a pounds 4m promotional to persuade shoppers to buy eggs again. Delia has provided an unexpected impetus to the process.
So how are the nation's chickens suddenly producing all these extra eggs? Egg production always runs at a slight surplus, with a certain number that are not shifted by their sell-by date. To avoid any risk of shortages in shops, sales earmarked for export or the catering sector are being diverted. But as Mr Berry says, "you can't turn the chickens on and off like baked-bean production". If egg buying turns into a frenzy, farmers will buy in more chickens from abroad.
Mrs Currie's notorious egg statement led to a pounds 40m scheme to prop up the egg industry as sales fell by up to 70 per cent in some places. Many schools took egg products off their menus. There was an estimated stockpile of 400 million unwanted eggs. Mrs Currie was forced to resign, despite figures released by the Department of Health showing that 7,000 cases of food poisoning had been firmly traced to contaminated eggs or chickens in the first 10 months of 1988, and the Ministry of Agriculture admitting it was only "the tip of the iceberg".
The salmonella issue refuses to go away. A survey by the Public Health Laboratory Service for the Department of Health earlier this year found that the contamination level in 1991 was one in every 650 eggs, but by 1995/96 it was one in every 700 - despite the slaughter, between 1989 and 1993, of 2 million chickens.
Last spring, Professor Richard Lacey, the microbiologist who first drew attention to the problem in the 1980s, said it was "endemic". The advice from the Egg Information Service, the promotional arm of the British Egg Industry Council, is that all eggs should be eaten within three weeks of purchase and kept in a fridge. Kitchen heat and variations in temperature provide conditions in which salmonella can grow. From the end of December, all eggs approved by the council will have a "best-before" date printed on them.
It is a far cry from the embryonic days of the industry in the 1920s, when almost all chickens were free-range. Then, they laid eggs for only six months of the year, but after the Second World War, with the dawn of intensive farming, that changed. By the 1960s almost 100 per cent of eggs were produced in battery farms. Now the pendulum is swinging back, though hybrid birds, including the isa, hyline, shaver, lohmann and hisex breeds, are still used for most intensive egg production, in which up to five chickens have to share a cage. Their free-range counterparts can roam around at 1,000 to a hectare. But both classes of chicken must be fed a purely vegetarian diet.
Although the decline of egg consumption is partly due to food scares and increased health worries about the effect of cholesterol, changing lifestyles have also played a role, according to Mark Williams, national egg specialist with the National Farmers' Union. "We have seen a decline in shell-egg consumption, but the number of eggs being processed is going up," he said. "People don't have time for a big breakfast anymore. We are eating out more, and restaurants are preparing dishes in which eggs may be a common ingredient."
So is the surge in egg-buying going to last? "We are absolutely delighted with what Delia Smith's show has done," says Tracy Rayne of the Egg Information Service. "In terms of boosting public confidence in the short term, this is very welcome. In the long term, who knows?"
THE CHICKEN ...OR THE EGG
There are 33 million hens employed in egg-laying in the UK. Battery farms account for the majority (83 per cent), followed by free- range (14 per cent) and barn chickens (3 per cent).
British hens laid 9.54 billion eggs last year; we ate 9.89 billion.
There are about 27,800 hen farms, the majority with 5,000 birds or fewer but there are 300 farms with 20,000 or more birds.
After their egg-laying days are over, most hens are "processed", their final destiny being pastes, pies and other manufactured products.
We eat 27 million eggs a day. Before the salmonella scare the figure was 30 million.
Retail sales account for 64 per cent of egg sales, catering 20 per cent and processing 16 per cent.
Brown hens lay brown or speckled eggs while white hens lay white eggs.
The nutritional content of an egg includes 11 per cent fat, iron, calcium, iodine, phosphorous, zinc, chromium and selenium, along with Vitamins A and D, plus Riboflavin. A sizeable egg contains 15 per cent of the recommended daily protein intake for women, 12 per cent for men.Reuse content