There are free-range organic, free-range, barn, woodland and "good value" basics. To add to the mix, increasing numbers of brightly packaged upstart brands have started to crowd the shelves, alongside exclusive supermarket own-label ranges. Yet the price differential between them is surprisingly small, ranging from £1 to around £2 for a half-dozen.
The surprise expansion of this once-fragile market is thanks in no small part to the massive popularity of television's The Great British Bake-Off (virtually every cake recipe requires eggs), and to celebrity-endorsed diets such as the pro-egg Atkins (being followed by the likes of Kim Kardashian).
Last year, a staggering 11 billion eggs were consumed in the UK, equivalent to 31 million a day, in one form or another. That number was up 6% on 2011. The vast majority are sold in supermarkets, with free-range the most popular. In fact, more free range eggs are now bought in Britain as a percentage of total egg sales than anywhere else in the world, despite being 50% more expensive than caged eggs.
It's believed the UK market will go increasingly free range as concerns over animal welfare supercede appreciation of more expensive organic production methods.
It would be easy to assume that for an established free-range egg producer such as Glenrath of Peebles, such near-saturation of a market it has dominated for 50 years might be enough to crush it. But that would be to underestimate its killer unique selling proposition: the brand founders' three granddaughters Amy, 23, Kitty, 22, and Lorna, 20.
The sisters, fronted by Kitty, have been instrumental in helping take the business founded in 1961 by their grandfather John and grandmother Cathy Campbell - and continued by their parents Ian and Agnes plus their aunts and uncles - into the 21st century.
The "eureka" moment came in 2010, as they were sitting with their parents round the kitchen table at their home in Kirkton Manor, near Peebles, discussing ideas for the future.
Kitty, a graduate of Harper Adams University in Shropshire, which specialises in agribusiness management, explains: "We were looking to create a unique identity in the market, which had become intensely competitive.
"We'd noticed that our competitors were using niche brands, and that they were proving very popular.
"We felt strongly that we had the knowledge and the skills built up over three generations, which made us pretty unique.
"Also, we are the only company in the egg industry that produces 90% of our eggs in-house. On top of that we felt we were meeting all the Scotland Food and Drink credentials of local and natural, and wanted to use all these credentials to give the business another edge. Amy also studied agri-business management at Newcastle University, and our sister Lorna is doing work experience on a dairy farm in Australia and we Skype several times every day. Between us we came up with the idea of the niche brand Kitty Campbell free-range eggs."
Tesco, the UK's largest retailer of Scottish eggs, whom Glenrath had been supplying with own-label free-range eggs from Isa Brown laying hens for 50 years, had also spotted a gap in the market. The girls were introduced to its specialist team for advice. Ten weeks after the initial meeting, in April 2011, Kitty Campbell had launched exclusively in Tesco stores in Scotland before expanding nationwide. The shelf value has shot up from £800,000 in 2011 to £2.8m in 2013 so far.
Kitty Campbell equates to 10% of all the free-range eggs sold by Glenrath, whose total production including organic, free-range, barn and good value is 1.4 million eggs a day. Thanks to the Kitty Campbell brand, Glenrath remains the largest free-range producer in Scotland.
It is in the process of further developing the new business by bulding a processing plant on the farm to supply liquid eggs to bakeries, and to develop Kitty Campbell-branded products such as meringues and macarons.
Kitty says: "Tesco were instrumental in helping us set up and we wouldn't be here today if it weren't for their support."
As production manager of 10 sheds situated around Peebleshire with a total of 320,000 free-range hens, Kitty works with a team of 15 helpers who meet every morning at 6.45am to start work at 7am, seven days a week. "My job is to make sure the hens are happy. That means checking and recording how much water they have, how many grams of feed they have consumed. Bright red combs are a good indicator of health, as are healthy feet and glossy, full coats of feathers."
The hens each lay an egg daily from the age of 18-20 weeks until they are 72-76 weeks old. These are individually sorted, collected and hand-stamped with the farm identity code (KC's is 1128SCO). At the grading plant in Penicuik they are given the British Egg Industry Council's red Lion Quality mark, and can be packed and delivered on the same day they were laid. The rather attractive egg tattoo guarantees it was produced in Britain to the BEIC's code of practice.
Red Lion quality eggs are subject to tighter controls on time, hygiene and temperature than laid down by the law. Although more expensive to adhere to, the red lion mark is crucial for a company that, like other UK producers, is facing a challenge from producers in the US, France and Spain - though they may not all comply with new EU leglislation that all caged hens should be raised in "enhanced colonies" with 25% more room than before.
Kitty says: "We know our welfare standards are the highest in Europe, and all our eggs are regularly inspected throughout the year to check we comply with the code of practice."
She points out that free-range hens are not as easy to control as barn-reared hens, a characteristic which can make life exhausting - as her Isa Browns were all too keen to demonstrate when we visited.
Rather than obey our command to gather round to have their photographs taken with Kitty, thousands of them made it clear they preferred to continue scratching about the farm among the heather, grass, gorse and thistles, pecking at the greenery and digging little dust holes and drinking water from puddles. When we tried to shoo them close to Kitty they would cluck, run and even fly away in defiance of our commands. They looked robust and happy.
"It's harder to manage free-range business because once you open the doors of the shed you lose control of your hens to a certain extent, whereas if they are kept indoors all day you can monitor everything they are eating and drinking. There are benefits to both sides of production; it doesn't change the make-up of the egg so it's really the consumer's choice.
"If you look after your hens they will look after you. On the other hand, unhappy hens won't lay any eggs at all."